The Extech MO25 is a lightweight, pen-styled compact moisture meter for wood and building materials. After selecting one of ten moisture levels, the user is signaled via audible alert and LED indicator lights that the object being tested surpasses the given threshold. This moisture pen features a data hold function, battery level check and automatically powers off when not in use. Use on wall board, sheetrock, cardboard, plaster, concrete, and mortar. Complete with two pins (installed), protective cap, built-in pocket clip, and one AAA battery.