Bluetooth 5.2 Sleep Headphones Wireless 3D Sleeping Eyeshade Music Headphones for Side Sleeper with 20 White Noise Timing Blue Item Type: Bluetooth Sleep Eyeshade Material: Ice Silk Cold Cloth Weight: Approx. 162g / 5.7oz Battery Type: Polymer Lithium Battery (Shipped With Built In Battery) Battery Capacity: 400mah Power Supply Mode: Type C Charging Bluetooth Specifications: V5.2, EDR, A2DP, AVRCP, HFP Frequency Range: 2.402GHz-2.480GHz Transmission Distance: More Than 20 Meters Sound Channel: Stereo Speaker Parameters: 32Ω 20mm Speaker Power: 2 x 10 Milliwatts Signal To Noise Ratio: 104dB Functions: Previous Song, Next Song, Volume Up, Volume Down, Play, Pause, Answer Calls, Make Calls, Timing Function Running Time: 15 Hours Charging Time: About 2-3 Hours