The early tan-colored Ibanez Tube King TK99's were designed by BK Butler, the person who builds the Tube Driver.

There are two different TK99's, one made in Japan and one made in the USA. The Japan model featured a noise suppressor while the USA Model didn't. Both had/have the same guts however from my understanding.

It's a great pedal and can run on 12AX7, 12AT7, or 12AY7 type tubes or the like. It also features a 3-band EQ to dial in some great tones.