digitsea Bluetooth Music / Running / Sport / Sleep / Sweat absorption Hat Cap Headband Headgear Earphones Headphones Headset With Microphone for Hands Free Call Answering (Medium Size Fits Most) blue 1.The most comfortable headphones to wear for running ,sport or sleeping. 2 .The headband made by comfortable sweat absorption knitted material. 3. Built-in Microphone for hands-free system,easy to dial or answer calls. 4.Built in high-capacity lithium battery,multi circuit protection,and can be recharged by USB port. 5.Bluetooth 3.0+EDR technology,compatible with most Bluetooth cellphone and tablet,such as samsung ,Apple etc.