Description: Unique in-ear design guarantee earphones closely fit to ears and will not fall off when you are working out. Meanwhile, audio performance has improved greatly.Main Features:- Waterproof and sweat resistant, no matter sweating in gym or running in rainy day, it will be with you.- NFC technology, isolate noise and let you immerse yourself in the music.- Wireless earphones, free from wired.- With drive-by-wire design, all in your hands.Specification:Bluetooth: V4.1Bluetooth transmission distance: 10mBattery: 45mAh Li-ion batteryTalking time: 4hStandby time: 100hCharging time: 1hCable length: 0.6mImpedance: 32 ohmFrequency: 20 - 20KHz 0.083 Package weight: 0.11 kg Package Size(L x W x H): 11.00 x 4.00 x 17.00 cm / 4.33 x 1.57 x 6.69 inches Package Contents: 1 x Earphones, 1 x English User Manual, 1 x USB Cable, 4 x Ear Hook, 2 x Earbud