Simple to attach, add-on boltless shelving conveniently extends the length of an existing starter unit for greater storage capacity. Attaches to existingboltless shelving starter unitto increase storage capacity Offers unobstructed visibility of items Made of 14-gauge, powder-coated steel 3/4"w x 2-5/8"hdouble rivet angle beams, adjustable on 1-1/2" centers Optional 5/8" thick particle board decking Configurable with casters (sold separatelyhere) To ensure rivets are properly set on posts, firmly tap beams with arubber mallet. Availability:Stocked in our warehouse. Ships next business day.