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The General Tools MMD4E is a professional-grade digital pin-type moisture meter designed for contractors and homeowners. It accurately measures moisture content in wood, drywall, and concrete with a broad range (1.5%-50%) using stainless steel pins. Featuring a large backlit LCD display with clear moisture level indicators and audible alerts, it enables quick detection of water damage and mold risk. The device comes ready to use with a 9V battery and extra pins, making it an essential tool for early water damage prevention and mold remediation.














| ASIN | B00275F5O2 |
| Batteries | 1 Product Specific batteries required. (included) |
| Batteries Included? | Yes |
| Batteries Required? | Yes |
| Battery Cell Type | Zinc Carbon |
| Battery Description | Alkaline |
| Best Sellers Rank | #709 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #1 in Moisture Meters |
| Brand | General Tools |
| Color | Gray |
| Customer Reviews | 4.5 4.5 out of 5 stars (14,839) |
| Date First Available | July 19, 2008 |
| Description Pile | Alkaline |
| Global Trade Identification Number | 00681035414477, 00885265551395 |
| Included Components | Moisture meter, batteries, extra pins |
| Is Discontinued By Manufacturer | No |
| Item Package Quantity | 1 |
| Item Weight | 5.6 ounces |
| Item model number | MMD4E |
| Lower Temperature Rating | 32 Degrees Fahrenheit |
| Manufacturer | General Tools |
| Material | Plastic |
| Measurement System | Metric |
| Mounting Type | Surface Mount |
| Part Number | MMD4E |
| Pattern | Digital Moisture Meter |
| Power Source | Battery Powered |
| Product Dimensions | 9.5"W x 1.4"H |
| Shape | Drywall |
| Size | Pin Type |
| Style | Digital Pin Type, Visual & Audible Alerts |
| Temperature Accuracy | 3 |
| Temperature Reading Accuracy | plus_minus_3_degrees_fahrenheit |
| UPC | 012301860924 716080037835 885312937219 885265551395 885367884865 681035414477 069060294668 031112659039 885898031110 522536779064 971483008299 031113382226 |
| Upper Temperature Rating | 60 Degrees Celsius |
| Usage | Inside; Amateur, Inside; Professional |
| Voltage | 9 Volts |
| Warranty Description | 1 Year |
G**H
Approve - Easy to Use
This Pin Type Moisture Meter is great! The size is comfortable and with just two features for testing WOOD or BLDG (Building Materials) this is very easy to use without over complicating it. 9V Battery was included!! The owners manual is available online at the manufacturer's website. Humidity will effect results which can vary depending on where you live. Overall, I approve this tool. Great value!!
U**N
Very accurate and helpful for detecting moisture issues
This moisture meter has been extremely helpful and easy to use. I used it to check different areas near the wall and floor, and it provided clear and consistent readings. You can immediately see the moisture level on the screen, which makes it very convenient for quick inspections. The device feels solid and well made. It responds quickly and gives accurate results, which is especially useful for detecting hidden moisture problems before they turn into bigger issues. I like that it has different indicators, so it’s easy to understand whether the moisture level is low, medium, or high. Overall, this is a very practical tool for homeowners. It helped me better understand the condition of my floors and walls, and I’m glad I had it on hand. I would definitely recommend this product to anyone who wants a reliable and easy-to-use moisture detector.
H**.
For professionals
It seemed to work ok but when I got my house tested by a professional the results were very different. I was easy to use however, you do have to make holes in the wall. Its battery life seemed good as well as calibration capability. I would only use if I was a professional. Otherwise do not waste your time.
H**I
Great product; it measures wood from 5 - 50% +/- 3% accuracy
We were getting hardwood floors installed - or so we thought - when the installers notified us that they could not do the installation because the wood in our house had acclimated to 6.4% moisture and our subfloors were at 12.8% moisture. The installer found a leak in our water softener line which we got fixed the next day. Unfortunately, we had no way of knowing (ourselves) when to call the installer back. Hence, we purchased this meter. As far as we know, it works great. We aren't too concerned with the overall accuracy of the instrument, +/- 3% is just fine for us as we're looking to compare the difference between two materials in our home (assuming the error is consistent between those readings). The resolution of the meter is 0.1%. Other things you might want to know: - It comes with it's own 9v battery. - It measures wood between 5 - 50% and 1.5 - 33% for other building materials. - It has a hold feature which allows you to save the current reading so you don't have to keep the meter jammed in the material you are measuring. - It beeps to let you know when it is done measuring. (Although, you can turn this off. We did accidentally and then figured out how to put it back on. We don't know why, but it has 8 different tones from which you can select.) - It has a toggle button between measuring wood and concrete (or other building materials). - The instruction manual is easy to read and follow. They come in English, French, and Spanish. - It uses a two pin system to measure the electrical resistance of the material between the two pins. This is then calibrated against moisture content to give you the reading as a percentage. This means that it will make two small pin holes in the wood you are trying to measure. Therefore, if you are concerned about the holes, consider a "pinless" moisture meter, which are much more expensive. The instruction manual lists other uses such as testing the moisture content of powders (for any scientists out there who need to measure such things for making standard solutions from scratch) and to test the dryness of a wall or furniture before painting or finishing. It also shows instructions for how to track down a leak using the meter. There's a funny picture in the instructions with the caption "be careful not to hurt your hands on the pins." Although, I did "test" the moisture content of my husband's leg. Don't worry, I didn't draw blood. Overall, for the price, the features, and the product functionality (so far), I would say this is a great buy. Also, we got it shipped quickly via Amazon.com. It arrived two days after we purchased it. Yay! UPDATE (7/31/2010): The pins broke when we were testing some brazilian walnut - one of the hardest woods out there. But I read in the instruction manual that pins were replaceable. I emailed General Tools through their website and got a quick email back. Less than a week later, I had two new prongs FOR FREE in my mailbox. Customer Service was AMAZING! The replacement prongs are much better than the ones that came with the meter. The new ones are shaped like little cones and have worked great on the harder woods.
J**A
Accurate as best I can tell
Works great. Seems to be very accurate at least as to seeing well under 10% moisture, very surprising, and the woods burns like proper dried
H**S
Must have
Fantastic tool to ensure you’re not jeopardizing the safety of your home and only burning wood that’s dry and ready to use. My chimney sweep recommended this to avoid creosote buildup. Affordable and easy to use
D**.
Pro quality
Good quality, works as intended.
P**T
It's the best from all th meters available in market
M**A
Easy to use with timber
A**E
Very useful and we found something not new damage in the wall we can’t see it but with this we discover it .
V**I
Die Funktion ist einfach und gut ablesbar, doch eine Beschreibung ohne deutsch ist schlecht zu gebrauchen. Das gesamte Ergebnis ist aber gut.
A**R
A protective carry case is needed
Trustpilot
1 day ago
3 weeks ago