Non-invasive moisture content measurements in wood/building materials. The MO257 Pinless Moisture Meter is for non-invasive measurements in wood and other building materials with virtually no surface damage. Measurement depth from 0.78 in. (20mm) to 1.6 in. (40mm) below the surface. Two user-settable alarm levels with audible beeper and visual flashing RISK or WET indicators. Triple backlit LCD. Complete with 3 AA batteries and pouch case.