Working Temperature: -10 - 55C Wireless Version: V5.0 + EDR Input: DC5V Speaker impedance; 320 Transmission distance: 10M Microphone sensitivity: 42 dB Usage time: 5-6 hours Frequency: 2.40 GHz Charging time: 1 - 2 hours Battery Capacity: 65 MAH / 950 MAH Standby time: 100 hours