2.4 GHz transmission frequency, Bluetooth wireless, around 30 ft. operating range. Operates up to 30 hrs. on built-in rechargeable Lithium ion batteries with a charge time of 4 hrs., 1 hour of charge provides up to 10 hours of playtime. Has headset power indicator, headset auto power off function, low battery indicator, and battery recharge indicator. Optional NFC Bluetooth pairing. Has power on/off and Bluetooth pairing voice announcements. Bluetooth connected Apple mobile devices using iOS Version 5 and above will show the battery level. Earcups swivel to flat for ease of carrying and storage. Machine washable ear cup pads and headband. Ear cup mini-jack output connection for second set of headphones.