Overview:Standard practice in the U.S.A. is to use crush washers, "O" rings and/or Stat-O-Seals to seal ports and banjo fittings. English practice is to use "Dowty Seals". Dowty seals are similar in concept to our Stat-O-Seals, but are considerably smaller in diameter (and thicker in cross section). Since many of our road racing and Indy cars— and their mechanics—are of English origin, Earl's offers a complete range of Dowty Seals. Features: English Practice Considerably Smaller Diameter Thicker In Cross-Section Complete Range Offered Application: Year Make Model Submodel Engine Size Universal Specs: Brand Earls Emission Code 5 Finish Natural Fitting Size #12 AN Material Synthetic Nitrile O-Ring in Zinc Plated Steel O-Ring Material Nitrile Product Line Premium Product Type Accessory Quantity Per Pkg. Two Washer I.D. 1-1/16 Inch