Specification: Brand: Xiaomi Color: White Size: 53.5*30*16mm Net weight: 40g Standby: About 10 days Normal use: About 1 week Keep talking: About 8 hours Battery: 4.35V 760mAh polymer battery Operating temperature: -10?-50? Communication network: GSM900/1800 Support for: Android 4.2+,IOS 7.0+ Features: Small and lightweight,easy to carry. Long time standby,can use about 10days. HD double way call,one key to dial. Anti-lost,protect your item when go outdoor. Pet anti-lost,like a fashion decorations. Low power consumption,ultra-low radiation. Warning: 1. You need to buy the standard Nano-SIM card to use with this product. 2. A mobile phone can bind 10 smart fixed position cellphone. 3. Can storage 20 phone contacts each smart fixed position cellphone. 4. Tracking mode can use over 1 day. 5. Only can use in mainland of China currently,we will upgrade it in the future. Package includes: 1 x Anti Lost Tracker 1 x Silicone Lanyard 1 x Manual