XO BE34 Smart Bluetooth Headphones with Long Battery Life,call time about 40 hours

■Bluetooth version: Jerry 6973D4 V5.0 Bluetooth profiles supported: HFP, HSP A2DP AVRCP ■Speaker specification: 10mm, 16 ohm brass horn ■Built-in battery: 3.7V/280mAh + ordinary protection board ■Shutdown standby time: more than 6 months ■Music time: about 40 hours (maximum volume) ■Call time: about