Set of 4 Scaffold Caster 8"x2" Polyurethane Steel Wheel Total lock heavy duty caster with 1100# capacity Each measures 8" x 2", 5-9/16" Swivel radius Roller bearing with 1-3/8" round stem with total lock brake Zerk in caster, Red polyurethane mold on steel core wheels Compatible with most major brands of frame and brace scaffolding