This is a set of magnetic sensing switches used to protect most doors and windows. The protective device monitors the opening and closing of doors and windows. High quality magnetic sensor contacts with strong, sensitive magnetic response and long durability. The wired part is often installed on the fixed door frame, and the coupling part is mounted in the corresponding place on the door. Easy to install and use. A good replacement for the old contacts. Simple to install with no hassle. Product Information Technical Product dimensions (L x W x H) 10.6 x 3.8 x 1 cm; 40 grams Item weight 280g Product Description: This set of magnetic sensor detectors includes the wired part and the mating part, which is ideal for installation on the doors of the house, garage, warehouse, business and store , etc Protect your home with this set of door security accessories. Features: This is a set of magnetic sensing switches used to protect doors and windows mostly. The protective device monitors the opening and closing of doors and windows. High quality magnetic sensor contacts with strong, sensitive magnetic response and long life. The wired part is often installed on the fixed door frame, and the corresponding part is mounted in the corresponding place on the door. Easy to install and use. A good replacement for the old contacts. Simple to install without worries. Specification: Condition: 100% Brand New Material: aluminum alloy Color: as picture shown Size (L x W x H): Approx. 106 x 38 x 10mm/4.2 x 1.5 x 0.4in Rated voltage: 12 V Rated current: 120mA Detection distance: within 50 mm/1.9 in Package included: 1 x set of magnetic detection contacts Note: Cannot be used alone. Should work with main unit of alarm system for alarm.