Mercury - High-Gloss Cowl Finishing Compound Engine Appearance Care Fine-Grit Formula 859026K1. Overview. There's something special about the moment you step back and see your engine cowl shine like it did the day you brought the boat home. It's a small thing, but it hits you right in the chest - that feeling of taking care of your gear because it's carried you through long runs, early mornings, and more memories than you can count. This Mercury Marine part brings that feeling back. The High-Glo