Speaker diameter: Φ 40 milimeters 
Impedance: 32 Ohms 
Sensitivity: 108dB S. P. L. At 1kHz; 
Rated power: 20mW 
Aggregate capability: 50mW 
Frequency Response: 20Hz-20, 000Hz 
Microphone Unit: Φ 6*5mm 
Impedance: ≤ 2.2KOhms 
Frequancy Response: 30Hz-16, 000Hz 
Operating voltage: 4.5V 

Description2.4GHz wirless Bluetooth headset 
1)Electric current(mA)47mA50mA 
2)Frequency range(GHz)2.404~2.4762.404~2.476 
3)Baud rate(BPS)Typ: 4M Typ: 4M 
4)Avaiable range(m)≥ 10 
5)Transmit power(dBm)73 
6)Receiver's sensitivity(dBm)-80-80 
7)Speaker sampling rate(kHz)44.1kHz, 16bit 
8)S/N ratioAudio-SNR@1kHz=-80dB Mic-SNR@1kHz=-80dB 
9)Charger power: Computer USB interface DC5V; DC5V(500mA); 
Travel charger; DC 5V (500mA)car charger 
10)Successive working time: About 8 hours; 
11)Battery: Rechargeable lithium-ion polymer battery (3.7V/320mA/h).