These extension brackets will work to fit a Front Runner Rack to vehicles with a gutter to gutter distance between 1450mm (57.1'') and 1685mm (66.3''). For example, a 1475mm wide Slimline II Rack can now fit a van's roof up to 1685mm (gutter to gutter) wide. Extension brackets bolt underneath the slats of Front Runner Rack and Front Runner Legs are fitted to the end of the extension brackets. Made from steel plates and 3CR12 stainless steel and finished in the same durable black powder coating as the Slimline II rack. Supplied with installation hardware and fitting instructions.