4consists of: flywheel, pn.9359815. Tire assembly, pn.9359813. Ring, retaining, pn.Ms217-1075. Axle, pn. 9359812. Key, pn.Ms20068-120. 3-screw, pn.Ms90727-13. Assembly to be dynamically balanced to .03 oz-in. At 3.250 + 50 rpm per mil-std-167-1, type ii.