38100.21.BL1 - Ajax DoorProtect Plus Jeweller Black is a wireless burglar alarm sensor for doors and windows with detection of opening, impacts, vibrations and tilts via magnetic contact and built-in accelerometer. The Jeweller technology guarantees encrypted communication up to 1,200 meters, anti-tampering and anti-jamming protection. Equipped with adjustable sensitivity, Chime function, dual magnet and NC input for external sensors, it offers battery life of up to 5 years. Easy to install via QR code and managed from the Ajax app, it is ideal for residential and professional security systems. Ajax