..it is not rust but old glue stains!

MXR DYNA COMP Compressor (the best) 1981 Block Logo Original not reissue wih orig. box

If you're looking for a transparent, colorless compressor, look elsewhere. The MXR Dyna Comp is a character, part of the legendary tone behind David Gilmour's soaring solos and countless Nashville chicken pickers. Though the compressor camps may be divided, there's no denying the massive following of Dyna Comp advocates who love the flavor of its squash.