Come with back plates for install on platform add in more force construction.Bracket mounts to hull or deck for attaching latch type boarding ladders and cockpit steps. 304 Stamped Stainless Steel Material,highly polished and attractive. Dimension:2-3/4" L x 1-3/8" W. Self-locking Keyhole design keeps ladder in place allows for easy ladder removal. Package contents: a pair of 304 Stainless Steel Mounting Sockets / brackets for Removable Folding Transom Ladders.