Du-Bro Kwik-Fill Fuel Cap Fitting Part No: 807. Fill your tank with ease directly from your 1 gallon fuel container. Just drill or cut a 1/2" \(12.7 mm\) diameter hole in the cap and install the fitting as shown. Features a safety fuel line storage fitting to prevent leakage. Works with gasoline or glo fuel. For glo fuel, use 5/32" ID \(medium\) silicone tubing. For gasoline fuel, use 1/8" ID \(large\) Tygon tubing.