Extreme Max 3000.3124 Slider Trax Marine Accessory Mounting Rails - 4' For boats without OEM rails  If a boat isnt pre-equipped with rails, Slider Trax rails install easily and allow users to add Slider Trax bases Construction: Aluminum rails are corrosion-resistant, lightweight, and strong OEM Approved: Available pre-installed on certain model boats from recognized OEM leaders Options: Slider Trax bases and rails are sold separately to maximize ordering options Warranty: Two-year replacement warranty