This is the extended-body version of the aluminium AN6 weld bung. The longer body is genuinely useful when the port has to pass through a thick tank wall, a double-skinned panel, insulation or a recess where a standard bung would sit flush and leave you no room to get a spanner on the mating hose end. It also moves the 37-degree flare seat further from the weld pool, which reduces the chance of heat distorting the sealing surface. AN6 suits fuel feed and return, power steering return and oil plumbing on typical street builds. Weld into aluminium fabrications only, in stages, and let it cool so the port stays true.