Specifications : 

Operating range 10 meters (33 feet) 
Paired devices Up to 8 devices - connected to two at the same time (MultiUse™) 
Talk time Up to 8 hours 
Music time - Wireless Up to 8 hours 
Standby time Up to 8 days 
Charging time Approximately 2 hours 
Weight 80 grams (2.82oz) 
Dimensions, folded (off) D 45mm x W 132mm x H 78mm (D 0.2 x W 0.5 x H 0.3 in) 
Dimensions, unfolded (in use) D 45mm x W 136mm x H 165-190mm (D 0.2 x W 0.5 x H 0.6-0.7 in) 
Dimensions, retail box D: 60 mm x W 155 mm x H 170 mm (D: 2.4 in x W 6.1 in x H 6.7 in) 
Microphones SLR = 14 dB +/- 3 dB 
2 pcs 4mm Omni-directional electret microphones 
Speaker 32 mm dynamic speaker 
R LR = -2 dB +/- 3 dB 
32 Ohm 
Operating temperature -10° C to 55° C 
Storage temperature -25° C to 80° C (max. 1 hr per day at max. temperature) 
Waterproof No 
Rain shower proof No 
AC power supply 100-240 V, 50-60 Hz 
Charging plug dimensions S tandard Micro USB 5 pins 
BT650s materials P olycarbonate/Acryl Butadien Styren (PC/ABS), Polycarbonate (PC), Poly Butylene Terephthalare (PBT), Polyoxymethylene 
(POM), Thermoplastic Elastomer (TPE), Thermoplastic Polyurethanes (TPU) 
Pairing passkey or PIN (if asked) 0000 
Features Answer call, end call, last number redial, mute, volume control, music track changes,Zirene® PowerBass