General Tools MMH800 4 in 1 Pin/Pad RH Moisture Meter
Ideal for locating water leaks and measuring moisture content of wood, drywall, plaster walls, carpeting, flooring, brick, grout, soil, paper, or powers, this unit features both pin-type and flat surface sensors.  It features tow displays; one for moisture content and one for ambient temperature and humidity.  The MMD800 provides a moisture level range of 5-percent to 50-percent in wood and 1.5-percent to 33-percent in building materials, and offers an audible indication of moisture level and storage of moisture level readings.