Description:-1. Bluetooth connecting, bluetooth v4.0 + EDR communication protocal could connect 5-8 anti-lost devices at the same time.-2. Powerful function, both-way junction(smartphone anti-lost devices could control each other).-3. Extraordinary working hours, our devices have ability to work about 6 monthes by CR203 button battery power supply, dont need to replace the batteries frequently.-4. Intelligent alarm, when the anti-lost device exceeds the set bluetooth range, the mobile phone and the anti-lost device will alarm at the same time; when the anti-lost device is disconnected,the map location can be checked on the mobile phone.-5. Anti-nuisance function, it can be set to mute for a certain period of time to prevent interruption during work and other important times;-6. Phone control, through the anti-lost device, users could control the phone shooting function, remote control selfie recording.Specifications:Communication Protocol: Bluetooth v4.0 + EDRMulti Task Management: one smart phone could manage up to 5-8 anti lost devices at the same time.Working Distance: about 20mApp Software: KindelfBattery Efficiency: CR203 button battery, lasting up to three monthsApp Voice: EnglishCompatible system: Apple IOS 5.0 or above / Android 4.3 and Bluetooth 4.0 or abovePackage Included:1 x Bluetooth Tracer(Included a CR2032 battery)