That's a regular hd450 headphone with HZR 414, a stereo control with buit-in dynamic compression for hearing impaired persons, with separate volume controls for left and right channel for balancing different hearing deficiencies of both ears. The plugs were cut to adapt a different type of jack, but never finished the job as bought a regular replacement cable which is provided ( so the headphone can be used as a regular one! )

As lightweight and supraural they are very comfy for  listening, the first thing that stands out are vocals and mids, they are the most dynamic there with some peak in the upper mids for a bit of shoutiness. They can sound like a good quality modern headphones there. 

With original box, in great condition - no scratches, no dents, almost like new, with new ear pads, too. 

Could consider posting it internationally but please, ask for a quote as the postage differs from country to country and the amount in the description is for European Union only, thanks.

 Technical details can be found on the box. 

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