Two 6-32 SHCS, a precisely machined steel hub on the flywheel face (.5002 OD) & a flange on the tapered sleeve which has a 1.125 in OD (.5000 ID), ensures positive location of the tapered sleeve each time it is mounted. The hub is #316 stainless steel & is shrunk into the flywheel before final machining. Notice the six bolt hole pattern used on the tapered sleeve's flange. This feature allows automatic positioning of the propeller to a horizontal position if the engine should stop suddenly at wide open throttle & prevents the hull from diving! It is used on solid drive shaft setups.
