What's the oldest piece of gear in your system?

This site is here for the buying and selling of Audio equipment. This causes me to wonder if most of us have relatively new equipment. If most of it is new, what is the oldest piece of equipment still in use, and why are you still using it?

My oldest piece is a Sota Star Sapphire, but it has been upgraded. It was originally purchased as a Sapphire in the 80's, but was upgraded to a Star Sapphire about two or three years ago.

What's your story?