Smart lanyard anti-lose elves: thin and smart, intelligent tracking, a key search and two-way reminder. When the anti-thrower is greater than the safety connection distance with the mobile phone, the two-way call alarm will remind you to check your belongings in time. Security: no cell phone can be found in the broken connection , and APP mobile phone can be found in the mobile phone. Strong : built in CR2032 button battery. Bundles of items and valuable items such as mobile phone, keys, handbags, wallets, etc. can be easily lost and reminders and lookup functions can be realized. Specification: Size: Approx. 38x38x7mm/1.49x1.49x0.27inch Material: PC + ABS Package Includes: 1 Piece Anti-loss device 1 Piece Manual Note: 1.Please allow 1~3 cm error due to manual measurement, thanks. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Please understand, thank you.