Replacement Caster - 3 x 1 1/4 * HD Casters Have Threaded Stem For Extra Security And Safety * All Single Wheel Castes Come With Removable Bolt And Locknut Allowing Disassemlby For Easy Cleaning And Removal Of Build-Up Grime Thread Or Anything Else That Your Wheel Picks Up During Normal Usage * This Caster System Will Add Longevity To Your Casters * Swivel: Double Ball Bearing With Hardened Raceways For Extra Strength * Cover: Helps Protect Swivel Bearings * Construction: Heavy Guage Cold Rolled Steel Formed For Strength