Cewaal&reg; Bluetooth Headphone, Stereo Headset Bluetooth Version 4.0 with Rechargeable Battery for iPhone 6/5s/5c/5,Samsung and Other Bluetooth Device (Black) 1. Deep-Sleep mode extends battery life (up to 14 days standby time, up to 6 hours talk time, up to 6 hours music play time) 2. Noise-cancelling microphone reduces background noise; Fits comfortably in either ear with a super soft gel ear tip 3. Enhance clarity on wideband-enabled smartphones, and Headset battery meter automatically shows onscreen for iPhone and iPad 4. Active pairing: Super easy and fast paring with your smartphone or other Bluetooth device; Multipoint technology, LED battery status indicator 5. Rouble shootings steps: (1)Make sure to FULLY charge the headset for the first usage;(2) Make sure the headset is linked to ONLY one smartphone. In order to link to a second smartphone, make sure to unlink the previous one;(3)The sound leve is 3-leve preset. Press once to lower or higher the volumn.