Simple Connection: Easy pairing Auto re-connection Great Voice Performance: DSP solution for echo cancellation and noise suppression Easy To Use: Caller ID sound prompt Music ring prompt Two buttons, same operation as mobile phone Dual microphones to provide the best voice and convenience Voice activation subject to voice activation enabled Multi-pair-up to eight devices Call rejection Last call number redial phones Volume control Specifications - Bluetooth specifications: version 1.1/1.2, class 2, 10 meters - Bluetooth profile supported: headset and hands-free Profiles - Operating frequency band: 2.402 to 2.480 Ghz ISM band - Input voltage: DC 12-24V - Dimensions (mm): 72 (dia) x 108 (dia) - Weight: 70gm