Item #F281 GE Protimeter Surveymaster specifications Model F281 (BLD5360) Gross Weight 3.5 oz (100 g) Dimensions (LxWxD) 6.8 x 1.2 x 1.9" (175 x 30 x 48 mm) Max. needle depth 0.4" (10 mm) Display LED and LCD Battery (included) 9V Measurement range    Pin (% WME) 0 to 99.9% Non-invasive (RF) 6 to 100 (relative) up to 3/4" (19.05 mm) deep Surveymaster includes: Heavy-duty pin extension lead 5" deep wall probes Wood calibration chart Calibration check device Spare pins Instructions Nylon carry pouch   Dri-Eaz presents the GE Protimeter Surveymaster Two great meters in one The Surveymaster offers two ways to monitor the moisture content of materials: penetrating pins and non-invasive radio frequencies. Use it to distinguish sub-surface from surface dampness, essential information when diagnosing the extent and cause of a moisture problem. Search Mode Detects moisture without making holes in materials, and independently of surface moisture. Uses non-invasive radio frequencies to search for moisture behind finished materials like ceramic tile and vinyl flooring. Measure Mode Penetrates materials with pin electrodes to take precise readings of moisture content in wood or Wood Moisture Equivalent (WME) in other materials. Virtual Training Center ~ GE Protimeter Surveymaster