Full length carpeted Centering Step Rails assists in centering your boat from side to side in rough water. Allows for easier access from dock to your boat, length of 8?, 9?, 10? or 12? depending which model of boat lift. Centering Rails for GM 1800 is part number 60-2035, for GM35120V is part number 60-2006, for GM 4500 is part number 60-2008, for GM 5500- 4500H- 6500H is part number 60-2010, for GM 8500H is part number 60-2059, and for GM 10000H is part number 60-2046. NOTE: ALL BOAT LIFT ACCESSORIES ARE AVAILABLE THROUGH OUR LOCAL 'FENDOCK' DEALERS. IF YOU NEED ASSISTANCE FINDING A DEALER PLEASE CALL US AT 1-888-336-3625 OR 613-722-6581