This is the Caroline Guitar Company Parabola solid state tremolo. It features an AM Amplitude Modulation mode as well as their FM Filtered Modulation setting. Caroline has always been known for their Havoc feature on their pedals, and this Havoc feature increases speed and cranks up depth for momentary bursts of the effect.
This Carolina Parabola Tremolo is in good condition and is fully functional. The original box is included.