What’s the difference between No.920 Marine Cleaner and No.631 Marine Compounding Polish?

No.920 Fiberglass Boat Cleaner is a medium cut, economically designed compound best suited for the removal of gel coat staining, mild-moderate oxidation and other surface imperfections that can be commonly remedied by hand use.
No. 631 Fleetcut’s versatility combines the cut of a compound with the finish of a polish. Designed for machine use (rotary for cutting, DA for polishing) No. 631 utilizes advanced abrasives specifically engineered to remove moderate-heavy defects; oxidation, minor scratches, swirls, stains and compound haze while leaving behind a professional, mirror finish.