This is an emulation of an Orange Squeezer guitar compressor, with added controls for tweaking. It runs in mono or stereo, and has selectable 2x oversampling. Note that this is not a studio compressor, the Vitamin C has the quirks and imperfections of the original Orange Squeezer that gave it its unique character.
The Orange Squeezer is a guitar compressor that was released in the 1970s as part of the Dan Armstrong effect line. It has been used prominently by artists like Mark Knopfler and Jeff Baxter for its smooth squish and sustain.