TWS wireless headphones are a type of headphones that connect without a cable not only to the playback device, but also to each other. They allow you to wirelessly listen to music, answer phone calls. The headphones are small, comfortable and reliable. The functions of the headphones are controlled by touch function buttons. The headphone case has a built-in 300mAh battery that allows you to recharge the headphones while traveling, training or walking. Bluetooth: v.5.0 Supports Bluetooth profiles: HFP,HSP,A2DP and AVRCP Bluetooth transmitter power: 3dBm Bluetooth transmitter frequency: 2.402-2.480GHz Operating distance: up to 10m Built-in rechargeable Li-Poly battery: earphones: 40mAh charging case: 300mAh Talking time: up to 4h Music playing time: up to 3h Charging time: around 1h Frequency range: 20Hz-20.000Hz Input voltage: 5V DC Included microUSB 25cm charging cable