Overview： PGDM Helmet Headset Bone Conduction Bluetooth Wireless Stereo Hands Free IP68 Waterproof Rainproof Motorcycle Helmet HeadphoneSpecification：  Item No.: Helmet Bone Conduction Bluetooth Stereo Bluetooth HeadsetTransmission range: 15 metersFunction: battery display, call function, support musicBluetooth protocol: 5.0Channel: StereoHow to use: head-mountedWhether single or double ears: unilateral hands-free