RWM"s 65 series caster features the patented kingpinless design, a single ball bearing precision machined raceway hardened to 53 Rockwell C. minimum. Swivel section features a 2-3/8" diameter raceway with 3/8" ball bearings. RWM patented this design that has proven itself to be the best solution for demanding applications. This is the caster design that all others are now copying because it is simply unmatched in extending service life and reducing all possible causes for caster failure. The 65 series is recommended for a wide range of industrial applications include dollies, utility carts, tow line and platform trucks. It is also ideal for: Tow lines, shock load applications and abusive conditions, production line dollies and trucks used in various industries including but not limited to: Boat and ship molding and building, Automotive, Aerospace, metal fabricating, metal forging, heavy machinery and equipment, military equipment, mobile homes, etc. Tractor pulled trailers, extreme duty platform trucks and material handling carts, air cargo and ground support equipment, storage tanks, gantries and heavy duty processing equipment, coliseum and gymnasium equipment, shipping/receiving carts, warehousing and freight terminal dollies and carts, and countless other heavy duty applications. Leg thickness is 1/4" formed steel. 1/2" Axle bolt and lock nut drilled with lube fitting, mounting plate size is 4" x 4-1/2" x 1/4" and 2" tread wheel.