Specification: Bluetooth version: V4.1 Bluetooth profiles: A2DP, HSP Frequency range: 2.4GHz-2.48GH Frequency response: 20Hz-20kHz Design: In-Ear Only Charging time: about 2 hours (Micro USB port for battery recharge) Noise Cancellation, Volume Control, Water Resistant Operating distance: up to 10m Talking/music playing: about 5 hours This is a new Sweat-proof Bluetooth 4.1 +A2DP Wireless Stereo headphone with best Audio Performance offering high voice quality and perfectly suitable for sports, supporting voice answering or rejecting the phone call by saying YES or NO. Enjoy it by running, mountain-climbing, etc! Features: With compact portable design Offering clear communication; It can be used as a headset and easily control music and phone calls Built-in rechargeable lithium-polymer battery Crystal clear sound: This item has the Bluetooth 4.1 standard and great audio performance will produce clear, full sound Wind noise reduction. The snug-fitting earplugs can ward off the peripheral noise and letting you enjoy your media free from distractions 11.5grams, probably the lightest headset in the world T-Light in-ear design to ensure long lasting comfort in rigorous environment Package included: 1 x Bluetooth sports headset 1 x USB Charging Cable 1 x User manual 3 pairs x Silicone ear tips (S/M/L) Note: Please kindly charge for it before you use it!