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The General Tools MMD7NP Moisture Meter offers non-invasive moisture detection up to 20mm deep with ±4% accuracy on wood. Featuring a 2-inch backlit LCD and a tricolor LED bar graph, it provides instant, easy-to-read moisture levels across multiple materials. Powered by a 9V battery, it includes smart functions like auto-calibration, hold, auto power-off, and low battery alerts, making it an essential tool for contractors, woodworkers, and inspectors who demand accuracy without surface damage.














| ASIN | B00HARYVUQ |
| Batteries | 1 9V batteries required. (included) |
| Batteries Required? | Yes |
| Batteries included? | Yes |
| Battery Cell Type | Alkaline |
| Battery description | 9V |
| Best Sellers Rank | 110,693 in Business, Industry & Science ( See Top 100 in Business, Industry & Science ) 5 in Lab Moisture Balances |
| Colour | multi |
| Customer Reviews | 4.3 4.3 out of 5 stars (4,536) |
| Date First Available | 2 Mar. 2014 |
| Included Components | ..... |
| Item Package Quantity | 1 |
| Item Weight | 113 g |
| Item model number | MMD7NP |
| Manufacturer | General Tools Mfg Co In |
| Material | other |
| Number of handles | 1 |
| Part Number | MMD7NP |
| Pattern | Detector |
| Plug profile | Freestanding |
| Power Source | Battery Powered |
| Product Dimensions | 2.87 x 7.62 x 16.51 cm; 113.4 g |
| Size | Pinless |
| Style | Digital LCD with Tricolor Bar Graph |
| Voltage | 9 Volts |
S**Y
Works well
Works fine for me!
B**B
A very good non-invasive meter
I already have a damp meter that uses two prods that need to be pressed on the walls. We have a wall that registers damp, and as such, the prods tend to make imprints in the relatively soft plaster, and after repeated tests, the wall becomes unsightly. This General Tools Moisture Meter works in a different way. There is a pad on the back of the device that just needs to be placed on the surface in question to obtain a reading. There is an immediate colour-coded response, and the definite benefit of this meter for me is that it can be moved across a wall, obtaining continuous readings, therefore easily identifying the limits of a damp area. The other meter I have needs to probe the wall, then be moved elsewhere multiple times, leaving the wall like a pincushion. The instructions for the meter confirm that the readings are not absolute, but their relative nature means that differences in moisture can be readily identified. Certainly the readings are very different from those on my second meter: where this one gives a 100% reading, the other is giving around 20%. So there's no need to panic at a 100% high reading. However, using this meter I have been able to establish it is a chimney flue simply by the dogleg route I have been able to locate. Recommended. It is an excellent meter; not definitive but certainly indicative enough to enable me to proceed with sorting out the problem.
C**E
Pleased
Pleased however metal mesh / beading or screws appear to set it off.
F**N
Life saver
Brilliant. I tested this device out on an interior wall that had slightly discoloured plaster work. After alerting me to the presence of damp I removed a small section of the wall and discovered that piping connecting to the shower was indeed slowly leaking. This device has potentially saved me a lot of hassle and money and that's the best endorsement I can give it.
K**R
Excellent for checking for damp.
Superb product, very easy to use. I got it mainly to check for damp in my caravan and it couldn't be easier. Simply select the material type you're checking and hold the device against it to get a reading.
D**E
Amateur meter not for professional use
Amateur meter not for professional use, I used this next to a MMS2 and it offered differing readings, this machine is OK for occasional domestic use but not for a professional.
M**N
Seems To Work And With No Damage To The Area Being Checked (No Pins)
For a while I have been concerned that the flat roof over the toilet is beginning to fail (ceiling has marks on it). I had a moisture detector but when I went to use it the batteries had leaked so it was knackered. Now I have this one which is pinless so you don't have to dig two pins into the surface you want to test. The sensing area is on the device back just a little lower than the display. On most of the walls I tested it reads 44% but when I go to the top corner it goes up to 87% and also starts beeping so I guess it's time for a new flat roof :( Interior walls read 20 to 25% As the reading is continuous you can just slide it along the wall or wood you are checking and note any changes in the reading. It also has a hold so you can lock the reading if you are checking somewhere where the screen cannot be seen. Comes with 9v battery and the only thing I would change is the scroll left/right which does not loop back.
Z**A
Four Stars
Did the job I wanted
P**H
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 :)
S**L
good
K**D
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.
S**R
Good product. I bought two pieces later. Good performance.
G**2
Exactly how it was described.
Trustpilot
2 days ago
4 days ago