Powerfin composite propellers offers a true Clark-Y airfoil which optimizes surface airfoil for thrust. Allows for infinite pitch range with any increment. The pitch alignment tool included, takes the guesswork out of pitching your prop. Simply set the stop screw, clamp the tool to the hub, and turn the blade to the stop. Powerfin features superior aerodynamics, noise reducing tips, superior composite construction, very strong low profile hub, durable finish, 2 and 3 blade configuration, fits Rotax® 75MM bolt pattern, adapters for every bolt pattern, 32" to 72" diameter, leading edge protection, speed set hub and a two year factory warranty against defects. Weight is 6.5 lbs. for 2 blades.