40mm dynamic speakers are combined with high quality Bluetooth V5.3, guaranteeing to deliver high quality sound perfectly.-Very quiet sound, good battery,Wireless Bluetooth headset with 3.5mm AUX input can be used as a wired headset.-The battery equipped with headset can provide up to 50 hours of music playback. -Carry the headset anywhere for a few days without worry about running out of battery midway.-isolates external noise with increased sound insulation.