The ATH-SPORT90BT wireless in-ear headphones are specially designed to bring high-quality audio reproduction to athletes and others with active lifestyles. Featuring high-sensitivity 6 mm drivers with a powerful magnetic circuit and dedicated headphone amplifier, the ATH-SPORT90BT headphones give you two ways to listen to your music: connect wirelessly to your smartphone or other Bluetooth® device; or store audio files on the built-in 4 GB music player and listen without an external device - no need to lug your smartphone around or worry about dropping it during workouts! The headphones come with the standard assortment (XS, S, M, L) of silicone eartips, plus four sizes (XS, S, M, L) of ear fins that secure the earbuds without wrapping around the ears. The cable rests comfortably behind the neck, its length adjustable via the cable slider. The in-line mic and controls let you easily answer calls, control your music, and activate the switchable ambient noise hear-through function for safer use outdoors. When you need a break, you can secure the ATH-SPORT90BT around your neck by linking the earbuds' magnet sensors, which automatically pauses music playback. The internal battery provides up to eight hours of playback from the built-in music player and five hours of wireless playback from a Bluetooth device. Additional features include IPX5 waterproof certification, so you can wash the headphones off when you're done working out; voice confirmation of various functions, including power on/off, Bluetooth connection status, and low battery level; and AAC codec compatibility, for better wireless sound quality. The headphones come with a 40 cm (16") USB-A/USB-C charging cable, and a carrying pouch.