Wireless bone conduction headphones with a built-in large battery, giving you battery life anytime, anywhere. Intelligent active noise cancellation reduces ambient noise and makes calls clearer. A new Bluetooth 5.2 chip, 1-second link, intelligent continuous connection, convenient and fast. Smart compatible, supports all mobile phones, tablets, laptops, and all mobile phones with Bluetooth compatibility. You can connect to Bluetooth-compatible devices simultaneously and switch between listening to songs, games, and calls at any time. The tight fit is waterproof and prevents sweat and dust from corroding components. Bone conduction hands-free car headset with microphone. Specification: Material: plastic + metal Size: LB-K3: 15 cm, X1: 15 cm, K69: 12 cm Color: black, white, green, pink Wearing method: bone conduction Acoustic structure: ring iron structure, closed Charging method: Micro USB Speaker unit: 16 mm Battery life: 10 hours Frequency range: 20-20KHz Package includes: 1 pair Notes: Please allow slight errors due to manual measurement. Different screens may display slightly different colors.