The Extech MO257 pinless moisture meter is a non-invasive meter that can monitor moisture in wood and other building materials with virtually no surface damage. The MO257 offers relative pinless moisture readings from 0.0 to 100.0 with 0.1 resolution and a measurement depth from 0.78" (20mm) to 1.6" (40mm) below the surface.

Other features of Extech MO257 pinless moisture meters include a multi-function, back-lit, triple LCD display; high-frequency sensing technology; automatic data hold; low battery indication; and auto power off. Two adjustable alarm levels with audible beeper and visual indicators (flashing "RISK" or "WET") alert the user of potential issues. The MO257 is automatically calibrated when the meter is powered on in dry air.