The Mercury Quicksilver 11-40140 Prop Nut is a quality boat part designed specifically for Mercury engines. This prop nut is essential for securing and maintaining your boat's propeller in place, ensuring optimal performance and safety while out on the water. The product is sold individually for $8, but you can also purchase a 4 pack of 2 for $24, providing you with multiple replacements on hand for any future needs. Plus, with free shipping included, it's a convenient and cost-effective option for boat enthusiasts and mechanics alike.