Sea Dog Portable Boarding Ladders4 and 5 Step Available. These portable emergency boarding ladder is made of molded-in, high-visibility orange polycarbonate with nylon rope supporting the frame. It secures quickly to cleats, railings, stanchions and halyards and will support up to 300 pounds. Part Number AB C D Steps582501-16"11-3/4"3' 2"2' 4"5582502-14-5/8"11-3/4"2' 5"2' 4"4