This Vevor outboard propeller is designed as a direct-fit replacement for selected Mercury and Mariner 90-400 HP outboard engines with a 4-3/4" gearcase and right-hand rotation. Built from high-strength aluminum alloy, it offers strong corrosion resistance for both freshwater and saltwater use. Its 3-blade 14-1/4" diameter x 21" pitch design helps deliver strong thrust, smooth performance, and improved fuel efficiency. The included M21 interchangeable hub kit supports secure installation, while the internal rubber hub helps reduce vibration and shock loads.