1. Main purpose is to prevent children or pets losing, purse or baggage being stolen, and valuable things leaving sw. 2. Environment friendly, without radiation 3. Search function 4. Ring and vibration 5. Sleek, compact, easy to carry 6. User can freely sate distance within a wide range(0~25m) 7. Diam,: 44h*28w*8d mm, 9.3g 8. 3v CR2032 Battery for transmitter, 1.5v AAA size for receiver