Features of the AKG K240 studio headphones include a removable cable and Varimotion technology for enhanced bass response. The headphones' integrated semi-open-air design incorporates a highly accurate dynamic transducer, and an acoustically tuned venting structure behind the element produces a naturally open sound quality. The circumaural (around the ear) pads are designed for hours of wearing comfort, while the K240's steel cable, self-adjusting headband construction and single-sided professional-quality audio interconnect ensure extended reliability in demanding professional studio applications. 55 ohm impedance.