LCD display with backlight Principle: Electrical resistance Wood Range: 4-75% Paper Range:4-90% Wall Range:0.2-24% Operation Temperature: 0℃to 40℃(32℉ to 104℉) Measurement Instructions: 1. Remove the cap to expose the needle electrodes. 2. Power ON the instrument. 3. Press "WOOD" key to test the moisture of wood,there are A,B,C,D, four wood calibration scales. Paper mode is used for testing Cardboard/Carton. Wall mode is used for testing Sheetrock/Wall Board/Floor. 4. Pushing the needle pins into the material and observe the reading. 5. Power off the instrument. Auto Power Off:This instrument will be Auto Power Off if there is no any button pressing in 5 minutes. This design is for saving battery power consumption Care and Maintenance: When the instrument is not in use, store the instrument in a stable, dust-free environment out of direct sunlight. Remove the battery from the instrument if it is to be stored for periods of more than one month, or when the low battery power symbol appears on the display. Battery Replacement: When the low battery icon appears on the display, replace the battery as soon as practical. 1. Remove the rear battery compartment cover. 2. Replace 3xAAA batteries(not included) 3. Cover the compartment door. Color: As Shown Material: plastic Package Contents: 1 x Wood moisture meter