DETECT MOISTURE- Determine the moisture content of softwood, hardwood and other building materials (like drywall and masonry) or check water damaged areas to see if moisture is still present | PROTECT WORK SURFACES - there are no pins on this tool, so your walls and projects can be saved from pinholes, scuffing and scratching to figure out their moisture levels | VISUAL AND AUDIBLE ALERTS - if you’re looking for the source of a leak behind your work surfaces, listen for the high pitch tones to give you an accurate read on where moisture is most concentrated or quickly see using the tricolor LED moisture indicator | DEEP READS - even without pins, this tool can read the moisture levels up to a 3/4 inch deep into the surface with an overall Measurement range of 0 to 53% for softwood, 0 to 35% for hardwood and relative readings for wallboard and masonry.Operating temperature: 32° to 122°F (0° to 50°C) @ <80% RH | EASY TO READ AND USE- Auto-calibrating, 2-inch diagonal backlit LCD screen and a 3-color LED bar graph, HOLD button, auto power-off function, out of range alarm and low battery, 9V battery included | FIRST STEP IN MOLD PREVENTION - by checking suspicious water stains with a moisture tester around the house, You can determine whether the area is wet (a perfect breeding ground for mold) or has long since dried