The General Tools pin type moisture meter with LED bar graph display is perfect for detecting the water content in a variety of materials to help ensure the appropriate level of surface dryness before painting, sealing or treating. Ten LED lights in green, yellow and red clearly indicate moisture contents ranging from 7 percent to 35 percent to help ensure precise readings every time. Whether you're a professional contractor or a conscientious homeowner, this ultra-sensitive moisture meter helps you easily detect hidden leaks in wood, plaster and carpet. This analog meter provides accurate moisture-level readings and is great for new home inspections, locating roof leaks or even selecting dry lumber at the yard. Use to detect water content in wood, plaster, drywall and carpet materials.Use in the restoration business to check if there is moisture in carpets and subflooring.Locates and helps identify water leaks in roofs, floors and walls.Reads moisture content over two separate ranges.Protective cap doubles as calibration checker.Equipped with replaceable 3/8 in. long stainless steel pins.Requires 9-volt battery (sold separately).Calibration Range: 21% +- 2%.