This Rack Kit is for truck camper shells and trailers that have roof top sizes no larger than approximately 1475mm/58.1'' (W) x 2368mm/93.2'' (L). The Slimline II Tray and eight (8) supplied Feet mount onto the OEM/Factory installed track of your canopy/shell or trailer.NOTE: Additional fasteners may be required to fit OEM/Factory supplied tracks.