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AcuRite 00613 Digital Hygrometer & Indoor Thermometer Pre-Calibrated Humidity Gauge, 3" H x 2.5" W x 1.3" D, Black

4.5 4.5 out of 5 stars 42,219 ratings
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Color Black
Brand AcuRite
Product Dimensions 2.5"W x 3"H
Item Weight 3.2 Ounces
Mounting Type Surface Mount

About this item

  • Maintain the Right Room Temperature and Humidity Levels: This wireless indoor thermometer/hygrometer combination is perfect to pair with humidifiers or dehumidifiers
  • Simple, Easy-to-Read Display Monitor: View current temperature and humidity at a glance with this indoor thermometer gauge and humidity sensor
  • Daily High and Low Indoor Temperature and Humidity Levels: Easily understand your range of conditions in any room with this home thermometer and humidity detector
  • Switch Temperature Readings Between Fahrenheit or Celsius: This wireless home instrument measures indoor temperatures from 32 °F to 122 °F (0 °C to 50 °C)
  • Sleek Design with Multiple Placement Options: Use the integrated keyhole for wall mounting, the magnet for placement on a metal surface (refrigerator or freezer), or the fold-out kickstand for use on any flat surface — the perfect desk thermometer
  • Indoor Thermometer/Hygrometer Measurements: 3" H x 2.5" W x 1.3" D
  • Company Based in Lake Geneva, WI, USA — Since 1943

Customer ratings by feature

Easy to read
4.4 4.4
Battery life
4.4 4.4
Temperature Control
4.2 4.2
Quality of material
4.1 4.1
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AcuRite 00613 Digital Hygrometer & Indoor Thermometer Pre-Calibrated Humidity Gauge, 3" H x 2.5" W x 1.3" D, Black

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From the manufacturer

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Product Description

An all-in-one digital indoor home thermometer and humidity gauge, the AcuRite Indoor Humidity Monitor gives you a full picture of your inside world. With an easy-to-read display, you’ll receive accurate humidity monitoring and accurate room temperature measurements. It features an indoor hygrometer for % relative humidity, an indoor thermometer gauge for temperature readings in degrees Fahrenheit and Celsius, a humidity level icon to indicate high, low, or ideal indoor conditions, and daily high and low temperature and humidity records. You can mount this indoor thermometer/hygrometer on a wall, stand it upright with an integrated fold-out stand, or place it on a metal surface like a refrigerator or freezer thanks to its magnetic back. Why use an indoor air monitor? Using a temperature monitor and humidity meter will allow you to ensure proper indoor humidity, which can yield skin, allergen, and other health benefits. Too much humidity can encourage the growth of mold, bacteria, viruses, fungi, mites, and other asthma-inducing agents. Overly dry air can lead to nose irritation, skin irritation, breathing difficulty, and damaging static electricity. Correct humidity can encourage plant growth and assists with the comfort and health of pets. Use this digital hygrometer to monitor a grow room in any location or as the perfect thermometer and hygrometer for a cigar room (humidor) or wine cellar. This humidistat, optical thermometer will help you improve your home environment through the power of knowing temperature and humidity. A perfect gift idea for new homeowners or for birthdays, Christmas, or Father’s Day, it comes with a one-year limited warranty.

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AcuRite 00613 Digital Hygrometer & Indoor Thermometer Pre-Calibrated Humidity Gauge, 3" H x 2.5" W x 1.3" D, Black
AcuRite 00613 Digital Hygrometer & Indoor Thermometer Pre-Calibrated Humidity Gauge, 3" H x 2.5" W x 1.3" D, Black
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Price$11.19-13% $19.99
List: $22.99		-28% $18.68
List: $25.99		-33% $9.34
List: $13.99		-20% $7.97
List: $9.99		-18% $17.99
List: $21.99
Delivery
Get it as soon as Monday, May 13
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Get it as soon as Tuesday, May 14
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Customer Ratings
4.54.5 out of 5 stars42,219
4.64.6 out of 5 stars4,233
4.64.6 out of 5 stars140,053
4.64.6 out of 5 stars140,053
4.64.6 out of 5 stars1,794
4.64.6 out of 5 stars6,022
Easy to read
4.4
4.7
4.5
4.5
4.6
4.7
Accuracy
4.0
4.4
4.3
4.3
4.4
4.5
Battery life
4.4
—
4.5
4.5
4.7
4.6
Quality of material
4.1
—
4.4
4.4
—
—
Durability
4.0
—
4.4
4.4
—
—
Sold By
Amazon.com
Intek
Intek
Intek
SECRUI
TOPOD
power source
Battery Powered
Battery Powered
Aaa Battery (Included)
Battery Powered
Battery Powered
Batteries
battery quantity
0 a, 1 aa
1 aaa
2 aa, 2 aaa
1 aaa
1 aaa
2 aaa
measurement accuracy
+/- 2 °F
±1°F/°C and ±2%-3%RH
—
1
±2~3%RH and ±1-degrees F
—
upper temperature rate
—
158 degrees fahrenheit
158 degrees fahrenheit
158 degrees fahrenheit
—
158 degrees fahrenheit
mounting type
Surface Mount
Tabletop, Wall Mount
Tabletop
Tabletop
Surface Mount
Wall Mount

Customer reviews

4.5 out of 5 stars
4.5 out of 5
42,219 global ratings

Customers say

Customers like the value, size and performance of the humidity meter. They mention that it's a great product for the price point, easy to place out of the way and that it works pretty well. They appreciate information, and readability. That said, some disagree on accuracy, quality, and temperature.

AI-generated from the text of customer reviews

6,960 customers mention6,090 positive870 negative

Customers like the performance of the humidity meter. For example, they say it works well, has a nice display, and has helped tremendously. Some mention they have had no problems with display performance. Overall, most are satisfied with the product's performance.

"...and gives you the current humidity in your home, records the highest and lowest results from the past...." Read more

"...Great buy for the home." Read more

"...flipped it off the table while I clean his tank and the thermometer is still working...." Read more

"...Yes, these work fine in the fridge and freezer!This give me a good idea when I need to heat up that room here and there to dry it out!..." Read more

2,502 customers mention2,266 positive236 negative

Customers find the humidity meter very easy to read, with a large display and nice interface. They also say it's simple and easy to use. Overall, customers say it’s a nice simple unit that isn't over engineered or overly complicated.

"...Very easy to read the large display of all the information it gives you...." Read more

"...This keeps me informed ro the humidity level in my house, easy to use, long battery life. Great buy for the home." Read more

"...This is very easy to do for anyone. Just put the AcuRite in the sealed bag overnight then check the RH reading the next morning and you are done...." Read more

"...The digital numbers are easy to read as long as I have on my glasses and I’m not in the dark...." Read more

2,170 customers mention1,941 positive229 negative

Customers like the value of the humidity meter. They say it's affordable, accurate, and worth the buy. Some mention that it saves them money on their electricity bill.

"...if you run a dehumidifier in your home or shop.. A really good deal for a quality product! Would recommend this to anyone including my friends!" Read more

"...It's worth the buy." Read more

"...and min humidity and temperature occurred within 24 hr interval and low cost...." Read more

"...This little device has been so handy and even saved me money on my electricity bill by keeping me aware of my heat usage...." Read more

891 customers mention775 positive116 negative

Customers like the size of the humidity meter. They say it's small enough to not take up much space, and it fits nicely by their computer screen.

"Easy to use, just the right size and price, bought before and will buy again when needed." Read more

"...Display is easy to read and the size is convenient. I mostly use them for my plants and have two of them...." Read more

"...and also has a nice little stand you could use instead. This unit is compact, easy to read and perfect as far as I'm concerned...." Read more

"...it anyway because it's such a small desktop monitor and fits nicely by your computer screen, on shelf, magnetic shelf, file cabinet, anywhere really!..." Read more

705 customers mention688 positive17 negative

Customers find the information provided by the humidity meter useful. They say it provides up-to-the-second information, as well as ranges for temperature and humidity over the past 24 hours. They also appreciate the highs and lows for the past day. Overall, customers say the meter is very helpful to have in the house.

"Does its job and gives all the details necessary." Read more

"...This little device has been so handy and even saved me money on my electricity bill by keeping me aware of my heat usage...." Read more

"These hygrometers are very helpful to have in the house. They are inexpensive but seem accurate...." Read more

"...Another Bonus I love is it gives you the highs and lows and now i have PROOF how miserable it gets at my desk sometimes ...and can either show the..." Read more

4,846 customers mention3,328 positive1,518 negative

Customers are mixed about the accuracy of the humidity meter. Some mention it provides very accurate humidity and temperature readings across a useful range, while others say the readings were not accurate and the absolute accuracy is in doubt. They also mention that the humidity number was so much larger than the temperature number and that it has a pretty large margin of error.

"The hygrometer is accurate and gives you the current humidity in your home, records the highest and lowest results from the past...." Read more

"We live in the woods so it is always damp. This keeps me informed ro the humidity level in my house, easy to use, long battery life...." Read more

"...those trying to learn the most basic humidity examples: Very low humidity can cause dry skin, nosebleeds, and who knows what else...." Read more

"...It has many readings that you need to know in order to keep your bearded dragons tank temps and humidity. It's worth the buy." Read more

1,788 customers mention1,205 positive583 negative

Customers have mixed opinions about the temperature of the humidity meter. Some find it accurate and gives a good general idea of temperature and humidity, while others say it's inaccurate and the display stops working past 45C.

"...The temperature reading is also quite accurate. It is very desirable to have a high accuracy humidity monitor and thermometer for use at home...." Read more

"This Accurite device gives me good general idea of temps and humidity. Accuracy not that important...." Read more

"...The temp is off by a few degrees but I have calculated it so that I am aware of the humidity level." Read more

"Love this temperature and humidity clock." Read more

1,662 customers mention870 positive792 negative

Customers are mixed about the quality of the humidity meter. Some mention it's well-made, reliable, and a high-quality gauge. However, others say that the build quality is poor and the product is not dependable.

"...I haven’t yet tried the product though I’m sure it’ll be good quality. This brand came highly recommended...." Read more

"...I've owned have had the exact same issue with the extremely fragile piece on the backside that allows you to clip it onto your belt, pocket, pants,..." Read more

"...I highly recommend these thermometers to any pet parent looking for a reliable and durable way to monitor their pet's enclosure temperature." Read more

"...More of a toy than a serious instrument. Not dependable - Not recommended.Note Jan 26.Forgot to mention it is !extremely!..." Read more

Excelente.
5 Stars
Excelente.
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Top reviews from the United States

Handgun Hunter.
5.0 out of 5 stars Accurate and small enough to put almost anywhere!
Reviewed in the United States on April 10, 2024
Verified Purchase
The hygrometer is accurate and gives you the current humidity in your home, records the highest and lowest results from the past. As well as the current temperature as well as keeping records of the highest and lowest readings. Very easy to read the large display of all the information it gives you. It's a must have if you run a dehumidifier in your home or shop.. A really good deal for a quality product! Would recommend this to anyone including my friends!
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KIM Bolin
5.0 out of 5 stars Must have
Reviewed in the United States on April 25, 2024
Verified Purchase
We live in the woods so it is always damp. This keeps me informed ro the humidity level in my house, easy to use, long battery life. Great buy for the home.
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S. Thornburg
4.0 out of 5 stars Considering the low price, this is a great little device!
Reviewed in the United States on December 17, 2015
Verified Purchase
Considering the low price, this is a great little device. When I first got it, about 60 days ago, I was extremely disappointed at the inaccuracy of it. Comparing it to other devices, the humidity and the temperature were each in error by close to 10 percent. However, I discovered that it was because I used a NiMH rechargeable battery, which is lower voltage than an alkaline battery (1.5v for alkaline, 1.25 for the NiMH I used). After 42 days, the device shut itself off completely; no "low battery" warning of any kind. When I replaced the battery with an alkaline AA cell, the temperature and humidity readings matched other devices closely. I experimented, trying different NiMH batteries, making sure they were fully charged. In each test, the temperature and humidity readings were off by about 10 percent when using a NiMH rechargeable battery, and the readings were accurate when using an alkaline battery. I would give this device 5 stars if the seller gave some information about the sensitivity to voltage; but they do not (as of December 2015).
Another experiment I conducted with this device was to place it in a plastic bag with a small packet of desiccant in the bag. The humidity reading did in fact drop quickly, and matched the readings of tests I conducted with other devices. When I buy herbs, I place them in double-zip bags with desiccant to help preserve freshness and to prevent mold. But I always wondered how much difference the desiccant really made, and how many packets would be required to significantly lower the humidity inside the bag. It turns out that one 10 gram packet inside a 1-quart zip-lock bag lowers the internal humidity to below 10 percent. The desiccant packets can be dried periodically in a low-temperature convection oven, and reused. The AcuRite device is small enough, and easy to read while inside the bag, so is helpful to me for gaining some data to help keep my herbs fresher.
6 people found this helpful
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Koiphish
5.0 out of 5 stars Yes... this is one of the few real reviews here on the great A mazon
Reviewed in the United States on April 7, 2024
Verified Purchase
How do you know I am real? Well I am such a nerd that I have about 10 of these! I put them in the freezer, the fridge and various rooms of my house. This is also one of the few products using s larger AA battery ... my nerd side again. I have food storage and find it important to keep track of any unfrozen events or extended warm fridge event during power outages so can guarantee food is still safe to eat! I also monitor humidity levels in unheated rooms to know when mold might be an issue (+80 humidity). Yes, these work fine in the fridge and freezer!
This give me a good idea when I need to heat up that room here and there to dry it out! Keep in mind the most humidistats are not so accurate above 80-90% ... it is just a rough level to trigger some action.
Remember to remove battery and reset after an outage event so you have a new record in the future!
So do you believe I am bit of a nerd and not a false review person yet!
2 people found this helpful
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Westsoc
5.0 out of 5 stars Calibration of AcuRite at different temperatures and humidifies using sodium chloride and calcium chloride saturated solutions
Reviewed in the United States on September 4, 2014
Verified Purchase
The first question ask by users of AcuRite humidity monitor is how accurate is the reading of relative humididty (RH) especially when the spec for RH is +-4% due to unit to unit variation. (Obviously, the company would like to ship all units they made to make more money. Tighter spec causes high rejects and the company will make less money or the cost for the AcuRite will have to go up.) Also the accuracy could degrade over time due to contamination of the humidity detector. There is no way for users to find out if they have bought an accurate monitor or one that is 4% or more off unless they do a two point calibration at room temperature using two saturated (with some undissolved salt left at the bottom) salt solutions each sealed in a ziplock bag together with the monitor. This is very easy to do for anyone. Just put the AcuRite in the sealed bag overnight then check the RH reading the next morning and you are done. Fortunately, the needed salts are also easy to come by as one is table salt (sodium chloride; the monitor should read 75% RH at 70 deg F) and the other could be driveway ice melt (calcium chloride; the monitor should read 31.5% RH at 70 deg F). Since bacteria could not grow in such salty solution, the sealed saturated solutions could be saved and reused over and over again allowing re-calibration whenever the user desires. I used two ziplock bag, each of which has two plastic cups. In one of these bags, each cup has 1/8 inch of water on top of 1/8 inch of undissolved table salt. Likewise, in the other bag each cup has saturated driveway ice melt solution.

The procedures I used to do a comprehensive calibration are given below.

Using these two saturated solutions, my measurements on the AcuRite I bought showed that for temperature from 39 deg F to 79 deg F and for relative humidity from 29% to 75% , the max error is 3% off in humidity occurred at very low temperature (39 deg F) (i.e 37%RH is actually 40%) and near room temperature, the error is only 1%RH. (Lucky me!)

Actually, the AcuRite is both a digital humidity monitor (hygrometer) and a digital thermometer. The AcuRite I tested is surprising accurate over a practical range of temperatures and a practical range of relative humidity values (see details given below). The temperature reading is also quite accurate. It is very desirable to have a high accuracy humidity monitor and thermometer for use at home. In the summer, a high humidity house is uncomfortable. Worse yet, a humid basement smells foul allowing mold to grow and humid closets cause clothes to smell bad - a nightmare for many housewives. Knowing accurately the humidity allows one to take measure to lower it. With seemingly high accuracy, the AcuRite is surprisingly cheap.

The comfortable relative humidly(RH) range to human body is recommended to be a region around 45%. American Society of Heating, Refrigerating and Air-conditioning Engineers Inc. (ASHRAE) recommends:

---RH ---------temperature ---- season
30- 60%----- 68-75degF -------winter
30- 60%----- 73-79degF ------summer

"Elevated relative humidity can promote the growth of mold, bacteria, and dust mites, which can aggravate allergies and asthma" and "Relative humidity levels above 70% may lead to the development of condensation on surfaces and within the interior of equipment and building structures. Left alone, these areas may develop mould and fungi." Typically, room temperature is set at 70degF. Also I preferred a RH of 50%. At 45%RH, I feel dry and my skin starts to wrinkle.

Sodium Chloride saturated solution is commonly used to calibrate a hygrometer (humidity monitor) at room temperature (70 deg F) which should give 75%RH. Thus the hygrometer needs to be calibrated again with another source with lower RH, such as Calcium Chloride (31.5% RH at 70 deg F) or Magnesium Chloride (33%RH at 70 deg F). If the hygrometer agrees with one of these values then one can assume it is accurate around 50% RH. If the hygrometer is used only at room temperature, it only needs to be calibrated by two saturated solutions (for example sodium chloride and calcium chloride). However, I have calibrated from 39 to 79 deg F.

Table salt (sodium chloride) and driveway ice melt (calcium chloride) provide an inexpensive and convenient way to calibrate (or check accuracy) of a hygrometer over a range of temperatures and humidity values. I have calibrated my AcuRite unit by using sodium chloride and calcium chloride saturated solutions, each of which was placed in a ziplock bag together with the AcuRite.

An accurate hygrometer is expensive and bulky and I was surprised at the seemingly high humidity accuracy of the Acurite which I purchased from Amazon. The attractive features of the AcuRite are: seemingly very accurate humidity and temperature readings across a useful range of humidities and temperatures(see calibrations given below), records the max and min humidity and temperature occurred within 24 hr interval and low cost. Also the display font for humidity is large enough for convenient viewing. These features are not expected from a $10 device.

Calibration using saturated table salt (sodium chloride) solution
Calibration is based on published measurements of equilibrium relative humidity(RH) vs temperatures above saturated salt solution by scientist(s). I will use these published RH values as standard. For table salt saturated solution, the published RHs, given below, surprisingly are almost a constant from 32 to 104 degF(the measurement increment was 5 degC).
Temp (deg F) RH(%)
32-59 76
68-104 75

I found that there was no different from using table salt with and without iodine. So I used the former. I also found that salt slurry did not work well. I sealed the AcuRite and two plastic cups in a ziplock bag which was further sealed by Scott tape. Each cup has at least 1/8 inch of undissolved salt (at the highest temperature of measurement) with at least 1/8 inch of water above it. Each deg F change can cause 3% change in RH. Since the AcuRite with battery is a big thermal mass, I made sure that for each measurement, the temperature and RH were stable for at least 1/2 hr, a condition which turned out to be most difficult to meet. Measurement results are given below. I found that for temperature, the AcuRite seems to be about 1 deg F higher than another temperature meter which has fractional deg F. However, I will use the temperature displayed by the AcuRite. Low temperature measurements were taken in a refrigerator. It took about one week to do all the measurements.

Temp (deg F) RH(%, measured) RH(%, from standard) Error(%)
41 74 76 -2
72 75 75 0
75 77 75 +2
77 76 75 +1
88 77 75 +2
90 76 75 +1

From the above table, at room temperature of 72 deg, the error is zero and from 41 to 90 deg F, the max error is 2%RH. I would say this is quite acceptable for home use. Next, I checked if the humidity is linear over a range of RH values and a range of temperatures by using another saturated salt solution.

Calibration using saturated calcium chloride (CaCl2) solution at low humidity
A better and purer source for calibration at low humidly is magnesium chloride. Over its saturated solution, the RH is 33% over practical temperature range. Pure Magnesium Chloride is available from amazon or ebay sellers. Another good source to use is Potassium Carbonate which another reviewer in this forum had used and which is also available from amazon or ebay. The equilibrium RH is 43% from 0 to 30 degC. However, I didn't want to spend the money and trouble to get them.
I found that I have some Prestone Driveway Heat ice melter (available from Home Depot and Lowes) which turned out to be Calcium Chloride. But the purity of the source was unknown and this would cast doubt on the results. From the internet, I found that the published equilibrium relative humidity(RH) vs temperatures above saturated calsium chloride solution are:

Temp (deg F) 41 50 59 68 77
RH(%) 40.0. 38.0. 35.0. 32.0 29.5
RH vs temp seems to be linear and the slope is bout -0.3%RH per deg F

My measurement results are:
Temp (deg F) RH(%, measured) RH(%, from standard) Error(%)
39 37 ~40 -3
79 28 ~29 -1

Thus at each temperature, there are now two data points.
If the calcium chloride measurements were believable due to the unknown purity of the calcium chloride source, then the linearity of the humidity of Acurite over a temperature range from 39 to 79 deg F and over a humidity range from 29% to 75% is quite good for home use as the max error is less than 3%RH occurred at 39 deg F, which is too low for normal use. Near Room temperature , however, the error is about 1%RH, which is remarkably small.

I believe that the humidity detector is polymer on a capacitor. Capacitor is a linear device and should response linearly to humidity absorbed. Thus for each temperature if two measured data points agreed with published data by other scientists, then it is sufficient to determine the accuracy and linearity at that temperature. I have verified the data agreement from 39 to 79 deg F. (Note that the calcium chloride purity is questionable. But the measured data did agree with published values.) Thus, within this temperature range, the AcuRite unit I bought seems to be accurate and linear. Ideally, one would like to further calibrate the unit with magnesium nitrate saturated solution which has a RH of 50-55% across practical temperatures. This would give three data points on a straight line to verify the linearity. However, I do not know how to get it easily and cheaply.

In Summary: for temperature from 39 deg F to 79 deg F and relative humidity from 29% to 75% , the max error is 3% off in humidity occurred at very low temperature (39 deg F) (i.e 37%RH is actually 40%) and near room temperature, the error is only 1%.

Max humidity
After I wrapped the AcuRite in a wet paper tower, the humidity was 99%, the expected value.

Update rate and modify the back cover to increase airflow through the unit
For normal use, no modification is need as modification does not change the accuracy of humidity and temperature. Allowing more airflow than necessary may shorten the life of the unit by quicken the contamination of the humidity detector inside the unit. Modification only changes the response time when the humidity changes. For home use, the humidity and temperature are not expected to change so fast that the unit could not keep up.
The unit updates the humidity and temperature about every 15 sec. After initial testings which showed that the unit was accurate, I invested time to modify the cover of the unit as the airflow through the unit is through a grill and could be increased to have a faster response time. Steps for the modification are given below:

1) The cover is held by 4 small screws. Remove them by a jewelry screw driver.
2) Separate the back cover from the main body gently and not too far apart as there is a ground wire of the battery housing connecting the two.
3) Remove the ground wire from the battery housing. Now the two parts can be separated.
4) There is a plastic stick used for changing deg C to deg F. It will fall out but is easy to put back during re-assembly.
I drilled four 3/16 inch holes on each side of the back cover as well as one 3/16 inch at the center of the back cover.

The above measurements were done on just one AcuRite which I bought. Because measured data points seem to agree with published values by other scientists, I am satisfied that the humidity and temperature of my unit are accurate and use it with confidence. However, beware that there are a large number of reviews in this forum who said their AcuRite is no good.
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William Grimes
5.0 out of 5 stars Works as advertised.
Reviewed in the United States on April 9, 2024
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Seems to be very accurate.
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Sandra Arrowsmith
5.0 out of 5 stars All
Reviewed in Canada on February 6, 2024
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Perfect for my needs
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Carlos
5.0 out of 5 stars Muito bom
Reviewed in Brazil on March 28, 2024
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Aparelho muito bom
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M. Romero S.
5.0 out of 5 stars El mejor y económico medidor de humedad, Super, Super recomendado!!!
Reviewed in Mexico on January 11, 2020
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Súper fácil funcionamiento, muy exacto y muy util!!!
Tengo ya tiempo con el y funciona de maravilla, estoy por comprar otro para otra habitación que requiero monitorear niveles de humedad.
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Giovanni Gotti
5.0 out of 5 stars Ottimo
Reviewed in Italy on January 28, 2019
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Funziona molto bene, la calamita sul retro è molto comoda.
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Robert Hopwood
5.0 out of 5 stars A good accurate tool
Reviewed in the United Kingdom on January 15, 2018
Verified Purchase
Having bought cheaper types to monitor the condensation issues in a 400 old house l found major differences in accuracy which defeated the purpose. This model was recommended on a website l was looking at so l bought it and quickly realised how good it was.Well worth the extra few quid.
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