Mercury - Tow N Stow Outboard Cover 200-300 Horsepower FourStroke Series Polysoft II Fabric 8M0221496. Overview. There's nothing quite like the feeling of heading home after a long day on the water-sun rinsed from the sky, the boat quiet beneath your feet-and knowing your engine is protected the moment you cover it. A good outboard cover gives you that small but meaningful peace of mind. It shields the most important part of your boat from sun, grit, and weather, and it lets you focus on enjoyin