Description -1. Connecting: The v4.0 + EDR communication protocol could connect 5-8 anti-lost devices simultaneously. -2. Powerful function, both-way junction(smartphone & anti-lost devices could control each other). -3. Extraordinary working hours, our devices can work for about 6 months with a CR203 button battery power supply, so we don't need to replace the batteries frequently. -4. Smart Alarm: When the anti-lost device exceeds 600 in, 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 time to prevent interruption during work and other important times; -6. Phone control, through the anti-lost device, users can control the phone shooting function, remote control selfie & recording. Specifications: Communication Protocol: v4.0 + EDR Multi-Task Management: smart phone could manage up to 5-8 anti-loss devices at the same time. Working Distance: about 20m App Software: Kindelf Battery Efficiency: CR203 button battery, lasting up to three months App Voice: English Compatible system: IOS 5.0 or above / Android 4.3 and 4.0 or above Package Included: 1 x Tracer(Included a CR2032 battery)