SoundBot SB220 Bluetooth Noise-Reduction Stereo Headphone for Music Stream & HandsFree Calling w/ 20 hrs Extended Talk and Playback Time, 400 hrs Standby time, Built-in Mic, A2DP, AVRCP, Chrome Stereo Bluetooth headset with back-hang style Foldable design provides maximum portability Features Software & CVC echo/noise reduction for reducing noise Wirelessly enjoy stereo music from all A2DP-enabled devices, such mobile phones, PDA, PC etc Switch automatically from remote controls on the headset allow you to play, skip and select your music tracks. Extended music playback time The latest version of A2DP1.2 and AVRCP1.0 profiles supportSupports Bluetooth Headset and Hands-free Profile(HFP 1.5) RF Frequency Range: 2.402-2.480GHZ, 2.4G ISM band Radio Performance: Receive Sensitivity of -90dBm, TX Power Max 4dBm Frequency Response: 20 Hz - 20 KHz, Very high Signal to Noise Ratio (SNR):95 Db, Total