Features: 1. Built-in 120 mAh battery, ultra-long standby 18h, to meet the use of various scenarios. 2. Bluetooth-compatible 5.1 chip, faster and more stable connection, to achieve synchronization of audio and video. 3. Large moving coil unit, full of detail tone, so you can experience pure sound quality. 4. Using bone conduction mode, no need to enter the ear, truly let your ears no burden. 5. If you have any questions after receiving the product, please feel free to contact us and we will provide you with a satisfactory answer. Specification: Bluetooth-compatible Version: V5.1 version Battery: 110MAH Talking Time: About 8 hours Music Time: About 8 hours Communication Distance: About 10 meters Frequency: 20Hz-20KHz Impedance: 32 Sensitivity: 85dB/mW Waterproof Rating: IPX 5 Speaker Material: Copper ring speaker 14.2mm Surface Material: ABS