In-Ear Headphones - Universal - Wireless Headset Folding Stereo Headset USB Bluetooth 5 Noise Canceling Headset Adapter with Microphone for Xiaomi Samsung TV Mobile Phone | Bluetooth Headset Highlights Universal Wireless Headset Folding Stereo Headset USB Bluetooth 5 Adapter Noise Canceling Headset with Microphone for Xiaomi Samsung TV Mobile Phone | Bluetooth Headphone Wireless Headphone Folded Stereo Headset USB Bluetooth 5 Adapter Noise Canceling Earphone with Mic for Xiaomi Samsung Mobile TV | Bluetooth Headphones & Headphones Bluetooth Version: V5.0 Frequency: 2.40GHz-2.48GHz Power: 4dBm, Class 2 Effective Range: 10-15m Sensitivity: 112dB Frequency Response: 20Hz - 20kHz S/N Note : 70 dB Distortion: 0.10% Speaker size: 40mm Transfer protocol: Support A2DP 1.2, AVRCP 1.0, HSP, HSF 1.5 Talk time: about 12-15 hours Music time: about 10-12 hours standby time: 300 hours Charging time: 2-3 hours Working current: 40 mA Operating temperature: -4~+131F (-20~+55C)