From David Clark at Amazon.com:Superior technology. Superior comfort. Superior performance. All in a sleek, new, supra-aural design. The new DC PRO-X from David Clark Company offers best-in-class Hybrid electronic noise cancellation and Bluetooth® wireless technology. Digital Signal Processing (DSP) provides high fidelity audio for superior communications and music listening. Dual voice coil ear phone drivers ensure fail-safe operation. And plush, leatherette ear seals and head pad to cradle you in comfort. All supported by a rugged, yet feather-light magnesium alloy suspension.