Safco Products 5283 Caster Set for Industrial Wire Shelving Starter and Add-On Units (sold separately), (Qty. 4), Black Optional caster Kit for use with Industrial Wire Shelf Post Frame (sold separately) Set of four 5" rubber wheel casters Weight capacity 1000 lbs. Assembly Required For use with Industrial Wire Shelving Models 5285, 5288, 5291, 5294, sold separately