Help identifying headphone extension cable

Greetings Fellow Audiogoners,

Can someone help me identify a headphone extension cable?

It has a black braided jacket and the inside feels flat rather than round. The only identifying mark is a perpendicular "T" with a curved (instead of flat) cross bar that is super imposed on what looks like a disected "Z" sitting on its side. This emblem sits inside a circle and is located on the male and female connectors (female connector is locking, lock is red)

I know I'm not giving you much here, but I also have no doubt some of you probably know exactly what I am talking about.

The cable was thrown in as a bonus when I bought some sennheiser HD 600's here on Audiogon. I was told it was a very pricy cable (more than $100 for a 7 or 8 foot extension!)

Any info will be much appreciated!

Thank You