Features:Bone conduction wireless earphones have a built-in large battery, providing you with battery life anytime, anywhere.Intelligent Active Noise Cancellation, reduces ambient noise and makes calls clearer.A new generation of Bluetooth 5.2 chip, 1 second link, intelligent continuous connection, convenient and fast.Smart compatible, support all mobile phones, tablets, notebook devices, and all mobile phones with Bluetooth compatibility.You can connect to Bluetooth compatible devices at the same time, and switch listening to songs, games, and calls at any time.The tight fit is waterproof and prevents sweat and dust from corroding components.Bone conduction car hands-free headset with microphone.Specification:Material: plastic + metalSize: LB-K3: 5.9in/15cm, X1: 5.9in/15cm, K69: 4.72in/12cmColor: black, white, green, pinkWearing method: bone conductionAcoustic structure: ring iron structure, closedCharging method: Micro USBHeadphone unit: 16mmBattery life: 10 hoursFrequency range: 20-20KHzPackage Includes: 1 pcNotes:Please allow for small errors due to manual measurements.Different monitors may display slightly different colors.