61902 Features: -Finds both wood and metal studs.-Patented SpotLite Pointing System, audio signal, and LEDs indicate stud edges.-Patented TruCal instant calibration.-Recessed LEDs for durability.-Continuously detects and warns of hot AC wires.-Detects the presence of unshielded, hot AC wires in all modes for safety.-Find wires in plastic conduit or NM wire.-Exclusive SpotLite Pointing System shines a bright beam of light over stud edges.-New updated industrial design.-Made tough to withstand daily jobsite use.-Non-marring wall pads.-Installing plasma and LCD mounts.-Installing wall or ceiling mounted projection screens.-Hanging pictures and mirrors.-Installing plant hangers, pot racks, etc..-Installing cabinets and shelves.-Installing ceiling fans.-Estimated battery life: 1 year at 10 minutes/day with alkaline battery.-Wood stud position accuracy: Typically within 1/8'' using dual scan and mark procedure, 3/16'' in DeepScan mode.-Metal stud position accuracy: Typically within 1/2'' using dual scan and mark procedure.-NOTE: Sensing depth and edge detection can vary due to moisture content of materials, wall texture, paint, etc..-Operating temperature: 20 to 120 F.-Storage temperature: -20 to 150 F.-Humidity: 80pct RH (non-condensing).-Water resistance: Splash and water resistant, not waterproof. Includes: -9V battery included.-Battery type: 9-V (included). Specifications: -Locates standard household 120/240V AC wiring.-AC position accuracy: Typically 90-250V at 50-60 Hz within 6 inches of hot unshielded wire. Dimensions: -Select between 3/4'' scan depth and patented 1 1/2'' DeepScan mode.-Dimensions: 6.07'' H x 2.7'' W x 1.18'' D.-Weight: 5.7 oz.-Depth: Typically up to 3/4'' in StudScan mode, 1 1/2'' in DeepScan mode.-AC sensing depth: In typical drywall with NM wiring, wires can be detected up to 3 inches deep. Disclaimer: -WireWarning lets you know you're working safe.