Perfect for watersports. Tough aluminium housing. Bluetooth and Charging: Bluetooth 4.1+EDR CSR 8635 Supports A2DP, AVRCP, HFP, HSP Up to 10m wireless range Bluetooth frequency range: 2.4 GHz-2.4835 GHz Up to: 8 hours playback / 250 hours standby time Charge time: Approx. 2 hours Charging input: USB DC 5V Battery: Rechargeable 100 mAH Li-polymer battery The Sandberg Waterproof Bluetooth Sports Earphones connects wirelessly to a Bluetooth device such as a mobile phone or tablet computer. Sandberg Waterproof Bluetooth Sports Earphones are designed to fit securely on your ears, so you can play sports without your earphones falling off. Waterproof and sweatproof for nearly any sports exercises, even in harsh conditions. Allows you to make hands-free and wireless calls.