Mercury - Vented Splash Cover Pro XS Series Polysoft II Marine Material 8M0228534. Overview. Any boater who spends long days chasing a tide turn or running across open bays knows how much abuse a high-powered engine takes. Spray, sun, salt, and the occasional bump from a loose fender all add up over time. That is why a dependable cover matters more than most people realize. When you slip this Mercury Vented Splash Cover over a 4.6L V8 225 horsepower Pro XS, it brings that quiet sense of confiden