Abstract: A caster assembly for engaging, lifting and roll transporting columns of support racks, such as warehouse pallet racks, for movement of the support racks, includes an adaptor bracket secured to a housing of the caster assembly for engaging holes arranged on a web portion of a two-lines-of-holes-type column. The adaptor bracket is secured to the housing using fasteners arranged through selectively spaced fastener holes through a front wall of the housing. For a line-of-holes single type column, the adaptor bracket can be removed and individual lugs can be secured to the selectively spaced holes of the housing which correspond to the hole spacing of the column. Thus, the same caster assembly can be adapted to engage a column of either type.