The legendary Stax SR-X Mk3 headphones, one of their best selling models and one that still sounds great to this day.  This is a 6 pin normal bias unit so it needs a matching amplifier/energizer to run.  The set charges up almost instantly and is perfectly balanced to my ears.  

Used set in good working condition, the earpads have been replaced with aftermarket units which are thicker for increased comfort.  

The headphone stand pictured is not included