Used Real Tube in good condition, this one has a Mesa 12AX7-A tube in it and sounds great.
About the Real Tube
Sporting five simple knobs, the Tube Works Real Tube overdrive, designed by B.K. Butler, is an intuitive, easy-to-use pedal. The Real Tube has knobs for output and drive, and controls for high, mid, and low boosts. This vintage pedal, designed and released in the '80s, has been used frequently by famous guitarists like J Mascis and others..