C.E. Smith Trailer Hub Kit Package 1-3/8" - 1-1/16" Stud. Simply remove your old hub and replace with this pre assembled and pre greased hub. Comes with dust cap cotter pin and wheel nuts. Spindle: 1-3/8" - 1-1/16" Bolt Cir: 5 x 4.5 Cap: 1750 Flange O.D.: 6-1/2" Max Wheel: 15" Hub I.D.: 1.98" Specifications for C.E. Smith Trailer Hub Kit Package 1-3/8": Manufacturer: C.E. Smith Color: Silver Package Contents: C.E. Smith Trailer Hub Kit Package 1-3/8" C.E. Smith 13511: Trailer Hub Kit Package 1-3/8" - 1-1/16" Stud