Bone Conduction Design: The sound transmits through the bone to the auditory nerve, no need to put into ear, no eardrum damage, good for the user to avoid ear disease and hearing losing. Ear-free Keeping Danger Away: Release your ears to listen to the world, you can respond to the surrounding situation quickly, far away from danger. Born for Sports: IP56 Sweat-resistant and 33g light-weight design immerse you in sports and music, suitable for walking, hiking, running, climbing, skating, driving, and other activities. BT 5.0 Connection: BT 5.0 ensures high data transfer speed, stable connection, and low power consumption. Free to enjoy hands-free calls or BT music via BT connection. Long Battery Life: 230mAh rechargeable Lithium battery provides up to 6 hours of playback time on one full charge and the standby time can last to 15 days.