Quick overview from the supplier:
Wireless Headset A4tech BH220, 40 mm driver, 32 Ohm, 100db, 204g, 40h, Foldable, ENC Omni-Directional Mic, Fabric Ear Pads, 400 mAh, BT 5.3, Black
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PECIFICATIONS
CONNECTION
Bluetooth Version v5.3
Operating Range Up to 10m (32 feet)
Built-in Battery 400mAh Lithium Battery
Playback Time 40H
HEADPHONE
Speaker Unit 40mm Hybrid Diaphragm
Frequency 20Hz - 20KHz
lmpedance 32ohm
Sensitivity 100dB
MICROPHONE
Mic. Type ENC Omni-Directional
Frequency 100Hz - 10KHz
Sensitivity -42dB
CABLE
USB Type-C Charging Cable 50 cm
