BMW bug with call back

* Dimensions : 50mm x 40mm x 15mm
* SIM Card slots – work with all GSM sim card
* Embed condense microphone.
* Microphone range: about 20 Meters (diameter)
* Receive sensitivity: -\+ 10K
* Working temp: -40~50 degree C
* Responding frequency: 1.2K~800Khz
* Stand-by time: 3-5 days (using voice control function); 6-15 days ( don’t use voice control function); 30-40 hours (flashlight available)