This is a compressor said to be modeled after the Dyna Comp. The condition is very good. It works without any problems. ~From the manufacturer's website~ ■ This compressor was developed with a focus on compression effects only, without any unnecessary tonal flavoring. It produces a wide variety of compressor sounds that you wouldn't expect from just two controls. ■ It naturally outputs everything from a light and responsive compression sound to a thick, deep compression sound that provides long sustain. ■ Thorough low-noise design achieves even more natural tone.