UIM class F1 and F2 racing propeller. Fits Mercury engine.

About size(pitch and diameter) and cupping:

Pitch determines the max speed that this propeller can achieve.

Blade area and Diameter affect grip. Bigger blades = more grip.

Cupping varies from 1-6, where 1 is very "slippery" and 6 has very good grip.

Blade area affects grip and bigger blades are more difficult to start up in water.

Recommended size is preselected for your convenience.

Photo of 3d model. Real product pictures are coming in future.