This is a resistor box that allows you to connect your Hifiman headphones to be used with a speaker amp. It takes in four 5-way speaker binding posts and outputs via 4-pin XLR to your headphones. This design allows for protection of amps and headphones by keeping the grounds separated and matches impedance. Normal price is $100. The condition is excellent on these, and since it only has wires and resistors, nothing can really age or break.
I'm also selling Moon Audio Blue Dragon 4-pin XLR cable that goes well with these for $120. Should you buy these together, I will sell both for $160, a savings of $30.
Free shipping and I'll pay PayPal fees. US shipping and PayPal only.