Abstract: A caster assembly mountable to a frame leg of a movable frame structure having a caster receiving aperture therein. The caster assembly of a preferred embodiment includes a caster having a caster fork, a caster wheel attached to the caster fork, and a mounting shaft attached to a caster fork. The mounting shaft is shaped and sized to extend through the aperture in the frame portion when the caster assembly is in an installed position wherein the caster is adjacent to a bottom side of the frame leg and an intermediate portion of the mounting shaft is adjacent to a top side of the frame leg. The mounting shaft has an generally flat blocking surface extending along a portion of the shaft such that the blocking surface is adjacent to the aperture in the frame leg when the caster is in the installed position. A locking washer is removably connected to the mounting shaft and is mountable to the frame leg.