Wallet Key Finder Two Way Bluetooth Intelligent Anti-lost Device 1. Power supply: contains a CR2032 button battery 2. Volume decibel: 90dB 3. Bluetooth frequency band: 2.4G 4. Bluetooth transmission distance: about 40m 5. Bluetooth version: 5.2 6. Working voltage: 3V 7. Material: ABS 8. Size: about 3.5 x 3.5 x 0.83cm 9. Weight: about 10 grams Features: 1. Press the anti-lost button twice, the device will make a sound, the LED will flash twice, and the mobile APP will sound an alarm 2. Click the call button on the APP, the LED of the anti-lost device will flash for 10s and sound a sound reminder, the more circles displayed on the APP panel, the closer the phone and the anti-lost device are 3. When the Bluetooth connection between the mobile phone and the item bound to the anti-lost device is disconnected, the mobile phone will automatically record the location of the disconnected item. 4. Positioning and tracking, mutual search, indoor range is about 5-20m, outdoor range is about 20-40m 5. Easy positioning, unobstructed communication, light and portable, disconnection reminder