Attwood Fuel Tank Fitting OMC/Johnson/Evinrude - Attwood fuel tank fittings and hose fittings are suitable for use with leaded, unleaded, ethanol blended and alcohol-blended fuels. Threaded fitting has 1/4in male NPT threads; barbed fittings fit 3/8in I.D. hose. Clamps are not included. 1/4in male NPT threads Suitable for use with leaded, unleaded, ethanol blended and alcohol-blended fuels