This Is the 5/16 x 24 Ninety Hub from Harry B. Higley. FEATURES: Aluminum construction. Made for .60 to 1.20 engines. Holes are predrilled for tightening purposes. INCLUDES: (1) Ninety Hub SPECS Shaft Size: 5/16-24 Weight: n/a Diameter: 1" Length: 1.5" NMH 2-23-98 ir/le kr3/26/03