General Tools Digital Moisture Meter MMD7NP - Humidity Sensor- Pinless and Non-Invasive

★★★★★ Excellent moisture meter — easy to use, accurate, and great for home protection This moisture meter is an outstanding tool for anyone who wants to protect their home, workspace, or renovation projects from hidden moisture problems. One of the things I appreciate most is how easy it is to use. The large 2-inch backlit LCD screen is clear and readable, and the 3-color LED bar graph gives quick visual feedback that makes checking surfaces fast and simple. The audible alert is also very helpful when scanning multiple areas. A huge advantage is the pinless design, which means it doesn’t scratch or damage walls, wood, or finished surfaces. That makes it especially useful for homeowners, contractors, and DIYers who want accurate readings without leaving marks behind. The deep-reading capability is another major plus, since it can detect moisture up to 3/4 inch below the surface. I also like that it works on a wide range of materials, including softwood, hardwood, drywall, wallboard, and masonry. It’s a great tool for spotting damp areas early before they turn into mold or more serious damage. Overall, this is a smart, reliable, and well-designed product that gives peace of mind and helps prevent costly repairs. Highly recommended!

Very useful and easy to use

This may not be the most precise sensor but it is accurate at being able to locate the source of a potential leak or at least tell you if there is an underlying problem. I like that it is non penetrating so it doesn't leave any damage to the walls or ceilings. I've successfully used it to help find water leaks/damage in drywall walls & ceilings (including textured) and also PLAM (laminate) countertops. It helped confirm that a section of counter was actually water damaged and not a fabrication error or other damage, which lead to thankfully finding the source of the leak.

Tested it on concrete interior wall to check for moisture content after a heavy rain caused the window seams to leak. The meter performed as expected over the suspected moisture accumulation behind the wall coating. There was moisture.back there. I tested it on a dry interior wall and it registered "0%" as expected. I would recommend this meter.

very pleased. bought it to check out houses as we were looking to buy one. simple to operate, seems to be good quality. and the AI questions sections on this Amazon website help explain a lot about its operation. My only quibble is that the LED screen is sometimes difficult to read from certain angles, but using the AI questions I just learned that that’s what the “hold” button is for! (place the unit to get a reading, pull it out while holding the hold button, and the screen retains the reading!). RTFM I guess. oh, also it’s important to keep the sensor area protected and clean.

My laundry room flooded and I'm replacing the flooring. The moisture is in the sub flooring - along with the existing flooring. The floor company told me to buy a moisture reader to monitor the sub floor, because they cant install replacement/new flooring until the reading is less than 5%. When I first got this reader it was over 50% on the sub floor, so I have been using heaters and fans. Now it is down to 25% - but the best thing is... I know nothing about flooring or moisture or how to use moisture readers, but this is super intuitive and easy to use. > Just hit one button to tell it what material it is "wall, hardwood, softwood", etc. then it's super easy - just lay the reader where you want it to read and it does the rest. > Seems very accurate. If i test, then re-test again, readings stay consistent. > Would be easy to locate a leak. You really do just run it over surfaces and it will change in real time. I personally dont have an active leak, but this is accurate and can pin point areas that are more moist than others. > In the video - the sub floor is less moist than the flooring that was soaked and is still installed. You can see how it detects different moisture levels in different areas. Very nice way to monitor as moisture levels go down. > OVERALL - so happy I went with this model, even though I was comparing it with a couple others that were a little cheaper. This one works VERY VERY well.. that's all that is important when your in a situation where you need one of these. If you buy a cheaper one, that may not be as accurate - you will be kicking yourself later when your entire project is up in the air and your going to spend that extra $10 at Starbucks because your stressed out and need coffee :)

This Moisture meter works fairly accurately on non-porus, completely plane level surfaces. You can not put it against an uneven surface (on the drywall setting) and get an accurate reading. I had previous water damaged sheet rock in my home, so I held the meter against the re-finished drywall to make sure no more water had penetrated the repaired roof, and into the sheetrock. The meter registered 0% moisture, which was a good sign. As I placed it on another spot on the wall, in an area that was previously never damaged - the meter read 12%. I scratched my head, and realized why it did that, and how the meter works. The meter works based on the penetrating ability, and the density of the surface. When you have broken surface tension such as on a piece of drywall - with a nail hole for example. I placed the meter over a nail hole, unknowingly, and got a 12% reading on an otherwise sold, (dry) wall. This is because the density change behind the sensor from the pinhole in the wall caused it to think it was seeing moisture. Get it? I have not tried it on firewood yet, I imagine the wood setting is programmed to come up with a way to take a measure of the area you sample, and feed you some sort of average for the uneven surface which you place it against. For this reason, I give the meter 3 stars. You can't really accurately measure the moisture content of any given surface with scientific like results without a probe which you would stick into the item. If you are aware of what you are measuring, and pay attention to the surface behind the meter - you may or may not get false positive results. For Masonry, it's also most likely a real gamble to trust the results of the meter. I don't regret buying it, You may also enjoy it - just pay attention to the surface you are placing it against and test several different areas and come up with your own average moisture. This is probably the best way to use this particular meter.

I bought the MMD7NP contact less moisture meter to measure wood moisture for woodworking projects. This product is working as described by General Tools. The product has two settings - softwood and hardwood. The technology used by contact less moisture meters is very sensitive to the woods specific gravity, which ranges from 0.17 for balsa to 1.1 for Ipe. The accuracy of this meter (and any meter) will depend on what wood species it is calibrated for. I called General Tools and got through to tech support immediately. The gentleman who answered the call knew what I was talking about, and provided the meters calibration species - Douglas Fur. This is the softwood setting, the hardwood setting just applies a conversion factor to the target hardwood species. Doug Fur has a specific gravity of 0.45 at 12% MC. I measure all moisture on the softwood setting, and apply a conversion factor depending on the species I am measuring. You can find the calculation online, and there are even online conversion tools. There are also online sources for properties of most woods. I was so impressed with General Tools tech support. We are all used to waiting hours on hold to get support, then getting someone who doesn't know what you are talking about. Not so here.

I bought this gadget to detect water leakage within the walls of my house. While the gadget works well, I am not too sure of the accuracy of its readings. Nevertheless, it serves well if you are interested in checking out for any water leakages without asking for true readings.

Good product. I bought two pieces later. Good performance.

Works fine for me!

Exactly how it was described.

Dood