Bekhic 3Pack (Upgraded Version) Personal Alarm for Women 140DB Emergency Self-Defense Security Alarm Keychain with LED Light for Women Kids and Elders Loop recording, automatic seamless video recording with the earliest unlocked video clips being overwritten by latest one when card gets full. Supports micro SD card with class10 speed or above, max. 32GB (16GB micro SD card included). Easy to install and use. Plug & Record. Dash cam will automatically turned on and start recording when the engine starts, and automatically stop recording and turned off shortly after the engine is off. Built-in G-sensor, capable of saving and locking the video recording data automatically in case of collisions; Pressing lock button can manually lock current recording video from being overwritten; Motion detection, any movement within the view range would trigger DVR to start recoding automatically when dash cam is on; Parking monitor provides 24/7 surveillance of your vehicle. All cameras are fully tested before delivery. With professional technical support+ always satisfied customer service+ 1 year warranty+ 1 month guaranteed return of goods.