This aluminum outboard propeller is designed for selected Mercury 40-140 HP outboard engines with a 4-1/4" gearcase and right-hand rotation. Its 3-blade design with a 13" diameter and 19 pitch is built to provide responsive acceleration and steady power delivery. The corrosion-resistant aluminum alloy construction supports use in both freshwater and saltwater conditions. An included M21 interchangeable hub kit helps provide secure fitment and easier installation. The internal rubber hub is designed to help reduce vibration and noise during operation.