In the realm of inboard propellers and ski wheels, we primarily see products made of Manganese Bronze VS NiBrAl which is an alloy blend with nickel, bronze, and aluminum. While the two look very much alike, nibral is considered harder, stronger and more corrosion resistant. To get technical, Manganese Bronze Alloy has a tensile strength of 65,000 PSI, and yield strength of 25,000 PSI. Nibral has a tensile strength of 90,000 PSI, and a yield strength of 37,000.

In accordance with those features, nibral does generally cost more and take longer to work on in the machine or repair shop. See our Full Blog Post on this question for more information.