RWM Casters Locking Stem Scaffold Caster, Swivel with Lock, Rubber on Iron Wheel, Roller Bearing, 500 lbs Capacity, 8" Wheel Dia, 2" Wheel Width, 9-1/4" Mount Height, 1-3/8" Stem Dia, 3-3/4" Stem Height 9-1/4" Overall height, 2-1/4" swivel lead and 500lbs capacity Rubber on Iron wheel with straight roller bearing Stem is 1-3/8" diameter 3-3/4" long with a 7/16" diameter hole drilled 2-5/16" up from the top plate Cold forged double ball raceway, swivel section is equipped with a lubrication fitting for field maintenance with 5/8" diameter bolt and lock nut kingpin Zinc plated finish to protect against corrosion