The ATH-ANC700BT QuietPoint® wireless over-ear headphones combine Audio-Technica's proprietary active noise-cancelling technology with Bluetooth® wireless technology and convenient touch and swipe controls. The headphones' noise-cancelling functionality is driven by a four-microphone (two in each earcup) multi-feedback system for wide-range performance that greatly reduces environmental noise. Features : - QuietPoint® active noise-cancelling technology powered by a proprietary four-microphone multi-feedback system greatly reduces environmental noise. - Bluetooth wireless technology with touch and swipe controls built into the earcup for answering/ending calls, controlling music & video playback and adjusting volume on connected devices. - 40 mm drivers deliver high-fidelity audio reproduction. - Included 1.2 m (3.9') cable with 3.5 mm (1/8") stereo mini-plug provides a wired connection for when wireless operation is prohibited (e.g., in airplanes or hospitals), when battery power is low, or when Hi-Res Audio is desired. - Foldable design makes headphones ideal for travel. - On a full charge, internal battery provides up to 25 hours of continuous use of Bluetooth wireless and noise-cancelling technology, and up to 1,000 hours on standby. Headphone Specification : Type : Active noise-cancelling Driver Diameter : 40mm Frequency Response : 5 - 40,000 Hz Sensitivity : 98 dB/mW (When noise-cancellation used)*1 95 dB/mW (When noise-cancellation not used)*1 Impedance : 150 ohms (When noise-cancellation used)*1 35 ohms (When noise-cancellation not used)*1