1. High quality polyester shell material + polar fleece lining material 2. Fashion and keep warm with answering the phone in winter 3. Bluetooth version, available for most bluetooth device like for iPhone 6 Plus & 6 / 5s & 5c & 5 /4s, Samsung Galaxy Alpha S5 / S5 Active S4 / S4 Mini / S3 / S3 Mini, Samsung Galaxy Note 4 / 3 / 2 4. Bulit-in Mic and stereo speaker, available for cell phone to transmit the speaking phone to your audio devices directly so that the user can answering phone 5. Bulit-in Li-ion chargeable battery, charge via USB cable, long stand-by time 6. Foldable for your easy carrying in you pocket 7. The magic Bluetooth earmuff is your best choice when doing outdoor sports like walking, hiking, Skating, cycling, touring, fishing, etc.