General Tools LCD Moisture Meter #MM8 - Leak and Humidity Detector - Pinless and Non-Invasive

The unit worked just fine and was quite useful from mid-March to mid-June. Then, suddenly something happened, and the sensitivity suddenly dropped on all ranges. it still feels the hand, but on the wall, masonry, softwood and hardwood shows only 0, where an hour ago I saw 15 to 55% of moisture. Replaced the battery with fresh one - nothing changes. Opened the case and did not see any broken wire. Actually, pretty nice design and well manufactured (I can tell that being a professional in engineering), but is completely useless now.UPDATE: contacted warranty department and they responded with the advice - recalibrate the unit. Pretty simple operation, and they attached the manual, so took about a minute to do. The unit works fine again, and I love the customer support!

Not sure how it works but it seems to work very well. Easy to use.

For the price, I did not think that this would be an ultra precise instrument, but for my use in determining if there is added moisture in new wood flooring over concrete and painted paneling over masonry, this device gave me an order of magnitude that I could determine where moisture might be accumulating in a room partially below grade. I like the fact that it does not have pins that must sink into the material's surface. The readings can vary by + or - 3% over the same spot over a few minutes, which is not precise. But since this device is determining the moisture in the material from a surface reading, it probably is as precise as I can expect and worked in the application I had.

This is a great little moisture reader.I have tried other models and they give you some numbers and different modes for different types of material but what do you do with the numbers??? what is a "normal" reading? etc...I used this to detect possible leaks in the walls.Most moisture meters out there tend to specialize for measuring moisture in wood and various material.This one works really really well for regular dry wall!You drag it slowly along the wall near areas where you suspect there might be a leak.For my part, it discovered that while there was no pipe leak, there WAS a lot of wicking moisture from the grout in the shower to the backing drywall material (an old shower without a waterproof membrane).The meter was VERY clear. In most area, it would show 0% moisture. As I approached the shower, it gradually increased all the way to 100%... There is also a color scale indicator (from green (OK) to RED... bad/wet!). And once you pass a certain level of moisture, the meter will also beep!Like I said... NO AMBIGUITY with this device.It will tell you in simple terms: You are OK or HEY! There is excess moisture in this wall!Verdict: GET IT!Get it if you suspect moisture or water leak in a wall.At about 20% moisture, you may start having some mold in the wall.This meter is affordable... it's worth having one on hand!

Metal studs behind drywall give false high moisture readings.

This is a wonderful tool. When I received it I was testing it on different areas in the house where there was water damage. It works perfectly. I even placed it on the toilet tank, etc. I was very impressed with the performance. I also purchased one for my sister.

Nice product and run well for moisture measuring

It does as it says and super affordable.