The USAMS US Series headset is comfort and great design in one. The headphones use Bluetooth 5.3 technology, which guarantees a faster connection than Bluetooth 5.2, stronger interference prevention and smooth sound. The headphones connect to your device over a distance of up to 10m. The battery in the charging case allows up to 35 hours of non-stop music playing if you regularly charge them using the case. The large battery capacity of 400 mAh allows the headphones to be charged five times, which will give you the possibility to use the headphones all day long. The device is equipped with a smart touch control that easily identifies commands - just tap the headphone and they will instantly respond to your every gesture. Product features: - Material: ABS + PC - Bluetooth version: 5.3 - Sensitivity: 108 ± 3db - Communication range: up to 10 metres - Speaker diameter: 13 mm - Frequency response: 20 Hz ~ 20 KHz - Impedance: 32 ? - Weight of headphones: approx. 3.7g x2 - Earphone battery capacity: 40 mAh - Playback time: approx. 7h - Charging case weight: approx. 30g - Battery capacity of case: 400 mAh - Charging time of headphones: approx. 1h - Standby time: approx. 40h - Size of charging case: 55.1 x 46.7 x 25.4mm