Features:100% brand new and high qualityFantastic guard for your houseSuitable for home and office but not for outdoor， it's not waterproofLoud alarm of 105dB to scare the intruderMagnetic sensorDistance between magnetic sensor and device should be shorter than 10mmMake sure the magnetic sensor and device are separate when open the doorPower Supply: 2xAAA batteries(Batteries are not included)Working Temperature: -10℃-60℃Working Humidity: ＜80%How to use:1.Make sure the device is not in guarding(LED flash every 3secs)2.Press No. 1 button more than 2secs and the device louds Bi， LED flahed， it gets into setting password3.Press old password(First time to set password is 1234)， after it louds Bi Bi， press new password， when it louds Bi Bi， it's finished4.Set the alarming time span， press No. 2 button more than 2secs and gets into setting，    press No.1 button and it louds Bi Bi Bi， the time span is changed to 0sec    Press No. 2 button and it changed to 3secs    Press No. 3 button and it changed to 5secs    Press No. 4 button and it changed to 10secs5.Organize/retreat a defense， press the on/off button when it's stanby state and it louds Bi Bi Bi，   it will be alert after 15secs and LED flash every 3secs，press password and on/off button to retreat6. Press password in 3sec and press on/off button after open the door to retreat the defense，    otherwise， it will alarm for 15secs every 30secs until the door  is closedColor: WhiteDevice Size: 4.2(L)x2(W)x8.2(H)cmWeight: 38g   Package Contents:1xMain Device1xMagnetic Sensor