Mirka Gel-Coat/Fiberglass Compounds

Mirka Polarshine: Professional-Grade Gel-Coat & Fiberglass Compounds

When it comes to restoring oxidized hulls, removing sanding scratches, and bringing a mirror-like gloss back to fiberglass surfaces, Mirka stands apart from the competition. Founded in 1943 in Helsinki, Finland, Mirka has grown into one of the world's largest and most innovative abrasive companies — and nowhere is that expertise more evident than in their Gel-Coat/Fiberglass Compounds lineup.

The Polarshine Marine System

Mirka is a global leader in surface finishing technology, offering a complete range of polishing compounds designed specifically for gelcoat, fiberglass, and hard-coated surfaces. Their flagship marine compound family, the Polarshine Marine series, is engineered from the ground up for the demanding conditions of boat restoration and production.

The water-borne, silicone-free Mirka Polarshine Marine polishing compounds range from Heavy Cut and Medium Cut to Fine Compound and Antihologram Polishing — removing damaged and oxidized surfaces, eliminating sanding scratches, and cutting the time required from start to finish. This means fewer steps, less labor, and better results whether you're working on a production boat line or a weekend restoration project.

Cut Levels Designed for Every Stage

Mirka's system-based approach allows technicians to select the right compound for each stage of the process. Mirka Polarshine 35 is a high-performance rubbing compound engineered for efficient removal of sanding scratches and surface defects on gelcoat and other hard coatings, designed for professional marine, industrial, and restoration use. For even more aggressive correction, Mirka Polarshine 45 is an extra coarse and fast-cutting polishing compound that helps save time while still achieving a perfect deep gloss finish.

Both Heavy Cut and Medium Cut are suitable for one-step processes, delivering a deep gloss when restoring a gel coat or topcoat surface. This versatility is one of the key reasons professionals across boatyards and marine detailing shops trust the Polarshine name.

Silicone-Free, Water-Borne, and Environmentally Conscious

Polarshine compounds feature a silicone-free formula suitable for professional workflows, with excellent control and reduced risk of swirl marks when used correctly. The water-borne, silicone-free, and sustainable Mirka Polarshine Marine polishing compounds reflect Mirka's broader commitment to reducing environmental impact without sacrificing performance.

Part of a Complete Finishing System

Mirka's product lineup is engineered as complete systems — combining abrasives, interface pads, sanding tools, and polishing compounds — to deliver predictable, repeatable results from initial sanding through final finishing. This means the Polarshine gel-coat compounds are designed to work seamlessly with Mirka's broader range of marine abrasives and power tools, giving professionals a single trusted source for the entire workflow.

Mirka polishing systems are trusted by marine professionals, boat builders, and restoration specialists who demand consistent, high-quality results on every job. Browse the full selection of Gel-Coat/Fiberglass Compounds or explore the complete Mirka brand catalog to find the right solution for your next marine finishing project.