A set of fittings for a fuel tank including an elongated stem and a ferrule. The stem includes an elongated coupling body at one end configured to couple within a cavity defined by an end of a fuel tank liner. The ferrule includes a ferrule body having a first ferrule end and a second ferrule end; a lip defining a coupling orifice at the first ferrule end with the stem being operable to extend though the coupling orifice and engaging the lip, and a ferrule cavity defined by the ferrule body that extends between the first and second ferrule ends and opening to the coupling orifice at the first ferrule end and a ferrule opening at the second ferrule end, the ferrule cavity configured to surround the end of the fuel tank liner.