Insert a GSM SIM card into the slot and put the audio bug at hidden place,then dial the card number to monitor your target,you will hear the sound arround the bug.(5-15m range) This cool spy gadgets looks like a normal car key,noboby will know it is a audio bug there.
Specification
* Frequency: GSM 900/1800/1900MHz
* Power Supply: Rechargable Li-battery
* Transmission Distance: Non-limit
* Card Compatible: GSM sim card
* Receive Sensitivity: ±10K
* Stand-by Time: 7 days
* Working Time: 4 hours
* Sensitive Range: 5-15m
* Product Dimensions: 50x40x25mm
* Working Temperature: -40℃ to 50℃
* Accessories: AC adapter,USB cable