Linkage TwoStep 2×2 progr. TwoStep 2X2 progressive linkage. 5 to 5-3/16 inch carb spacing. Fits 4-cylinder equalizer and Riley Two Port 2×2 intakes (5in) plus most 2×2 adapters designed for 4bbl carb intakes (5-3/16in), and Vern Tardell Slingshot 2×2 adapter (5-3/16in). To use with banjo fittings, add 9086K spacers (Vintage Motors’ SKU #3119). Sold each.