The MO57 take pinless (non-invasive) Moisture measurements on wood and building materials without damaging the surface with the depth of approx <4" (100mm) with Extech’s MO57 Moisture Meter. The ball moisture sensor provides smooth gliding on hard or delicate surfaces. Easy-to-operate with display icons that indicate the levels of moisture content plus audible alert feature. Ideal for building restoration projects and applications where moisture detection on floors, tiles and under carpets is critical. A musthave tool for analyzing the after-effects of water leakage behind walls and in ceilings and also measuring moisture content on a non-flat surface