Audio-Technica ATH-SR5BTBK Bluetooth Wireless On-Ear High-Resolution Audio Headphones with Mic & Control, Black Bluetooth wireless technology that can pair with up to eight Bluetooth wireless devices Mic and volume/control switch built into the earcup for convenient control of smartphones and other Bluetooth wireless devices NFC (Near Field Communication) functionality enables touch pairing with NFC-compatible Bluetooth wireless technology devices Large 45 mm drivers for outstanding sound quality and are capable of Hi-Res Audio (540,000 Hz frequency response) when used with the included cable Soft, memory foam earpads and easily adjustable headband slider provide a comfortable on-ear fit Internal battery provides 38 hours of continuous use (1000 hours on standby) on a full charge