Compatible with Interlogix learn-mode panels and receivers, the TX-E Series Recessed Wireless Door/Window Sensor has a standard flanged top and compact design, allowing it to be well hidden within the door frame. It's a perfect solution for when discrete sensors are needed because it's practically invisible when the door is closed. It comes with a replaceable lithium battery that can lasts up to five years under regular usage for dependable, long-lasting operation. Increase Your Safety & Security With Interlogix: Formerly GE Security, Interlogix's robust product offering is designed to protect and secure your business, your home, and your family. Their products are leading the industry in innovation and reliability. Whether it's a complete system, access control, motion detection, or simple magnetic contacts, Interlogix has the products that will meet your security needs. Specifications. Manufacturer part number: TX-E221. Frequency: 319MHz (crystal based). Battery: CR2 (included). Battery life: 5 years (normal usage). Magnet type: N48 rare earth. Magnet gap: 1 inch maximum. Operating temperature: 32 degrees to 120 degrees F (0 degrees to 49 degrees C). Operating humidity: 5-95% non condensing. Dimensions of sensor: .75(W) x 2.5(H) inches (1.905 x 6.35 mm). Dimensions of magnet: .75(W) x 0.5(H) inches (1.905 x 1.27 mm). Weight: 1.4 oz.. Approvals: FCC/IC. Warranty: 2 Years.