The Catalinbread Topanga Spring Reverb is based on the sixties outboard Fender spring reverb units. These units differed tonally from the in-amp ones since the reverb would be driven by the front end of the amp providing a more intense sound. The Topanga is meant to emulate that specific sound, while also giving you control of a discrete preamp to push the front end of an amp harder.
This unit is in excellent condition with no blemishes and has Velcro on the bottom.