Sennheiser HD 400S wireless speakers Proof of original purchase is

Proof of original purchase is required

Signal-to-noise ratio    >85dB

enabling the digital output from both coaxial and optical sockets to exhibit vanishingly low levels of jitter (digital distortion)

Power Recommendation: 100W or more per channel power amplification is recommended to experience the best quality and performance

95% of pollutants as small as 0

Sennheiser HD 400S wireless speakers Proof of original purchase isLightweight, foldable headphones The HD 400S features a one button smart remote, which allows you to control music and take calls with ease, and the sturdy folding design makes these headphones durable and compact enough to be taken anywhere.