"The SOLAS Nissan/Yohatsu Type C 35-55hp Fixed Hub Propeller Hardware Kit sets you up to install a new boat propeller (not included). This kit is specifically built for SOLAS Dual Prop and B3 installations, and front and rear propellers must both be manufactured by SOLAS. Also, they must be made of the same material: either aluminum or stainless steel but not both. Special tools may be required. Please consult OEM manual for proper installation and torque specs. Engine fitments include: 13-tooth spline 3.50"" gear case; 35hp (35B only) through 1984; 40hp 1984 and newer; 50hp 1992 and newer; 50hp (50C only) 1987-91; 55hp 1981-88; 60A 1986 and newer; and 70A and 70B 1981 and newer. Kit includes 2 castle nuts, 2 thrust washers, 2 spacer pins, and 2 cotter pins. Kit sets you up to install a new boat propeller (not included) Built for SOLAS Dual Prop and B3 installations Includes 2 castle nuts, 2 thrust washers, 2 spacer pins, and 2 cotter pins"