New Big BT300 Over-ear Bluetooth 4.0+APT-X Headphones headset---Clear Talking and Music Bluetooth 4.0 +apt-X Stereo Headphones- Advanced Bluetooth 4.0 Latest technology The Newest advanced bluetooth 4.0 +apt-X technology(8 times the bandwidth compare over the bluetooth 2.1 standard)! Built-in 4 microphone Allows clear Phone communication; Enables use as a headset. Music and phone controls ensure ease of use Built-in rechargeable lithium-polymer battery With Li-battery enables up to 12 hours of talk time or audio playback, Standby time up to 300 hours. Passive noise reduction Up to 15dB blocks background sounds for an immersive listening experience. Noise Blackout with dual microphone technology promotes optimal call quality.