Features:  - Bluetooth connection:  Connect with the Bluetooth function of the mobile phone, and the two-way search function can connect 4 anti-lost devices at the same time.  - Alarm function:  In the connected state, when the anti-lost device exceeds the set Bluetooth range, the mobile phone and the anti-lost device simultaneously alarm.  - Accurate search:  On the mobile phone, you can check the map positioning when the anti-lost device is disconnected.  - Silent design:  Provides the do not disturb function, can set the mute within a certain period of time to prevent the work and other important time to disturb.  - Remote self-timer:  Control the phone shooting function through the anti-lost device, remote self-timer.    Specifications:  Color: Black，White，Blue;  Material: ABS;  Battery type: CR2032;  Standby time: 12months;  Buzzer: 90DB≤;  Working voltage: 3V;  Working time: Depends on actual using condition;  Battery capacity: 200mAh;  Working range: 20-50m No barrier，Max up 100m;  Bluetooth version: BLE4.0;  Name of software: iFindU;  APP connecting current: 26-70uA;  Frequency band: 2400 – 2483MHz;    Package included:  1 * Smart Alarm Device;  1 * Manual;    Note: The product needs to download APP to use.