1、Ultra low power design, the battery can stand for 2 years. Import key components, fire flame retardant housings; 15 millisecond fast response, no delay in use. 2、The door alert is loud, and you can choose from various ringtones and tones using ringtones applications. 3、You can also adjust the volume of each ringtone. If someone is forced to open the door, will give an alert and give you a better sleep experience at night. 4、Switch the cloud history record, let you master the time of each switch of the door and window, and traceable for each switch. 5、The sensor is a mini, not only can be installed at the door and windows at home, but also can stick to drawers, file cabinets, mailbox, etc. 6、Door and window sensor, easy installation with sticker, can also be fixed by mounting screws. Item Type: Door Sensor Material: ABS Battery Model: CR2 x 1 (Without Battery Delivery) Maximum Allowable Installation Gap: <10mm/0.39in Stand-Up Current: 13uA Alarm Current: <30mASupport: For google, Tmall Genie 2 x Sensor 4 x Screw 4 x Expansion Tube 1 x Manual 2 x Sticker