Guardian for doors, windows, and valuables DoorProtect Jeweller is a wireless opening detector designed to secure doors, windows, and skylights by detecting intrusion or burglary attempts. It features a British-made reed switch rated for over 2 million openings. The detector comes with magnets of two sizes for flexible installation even on narrow window and door frames. DoorProtect Jeweller is powered by a pre-installed battery, ensuring operation for up to 7 years.
eBay