Specifications: Bluetooth: V4.1 Sound Track: Mono Battery Capacity: 150mAh (Poly-ion) Talking Time: 9h Playing Time: 10h Charging Time: 2h Standby Time: 320h Transmission Distance: 10m Features: Unique Foldable Neckband Headphone Style: You wear the Earphone around your neck like a necklace ,which decreases pressure on your ears and the Headset won't fall off when you're doing exercise. Meanwhile ,you can fold the earphone anyway you want due to the flexibility of the material. Lightweight Environment-friendly Silicon Neckband: Won't cause any damage to your skin when you're doing sports. Noise Cancelling: Helps you fully enjoy the music. Sweat proof: Sets you easy from the worry of sweat damage when you're jogging, doing yoga. Compatibility: Compatible with most of the Bluetooth-enabled devices Magnetism: the two earbuds can be brought together through the magnetism of each earbud, which makes the earphone portable.