A stainless weld-in bung producing a male AN8 flare port. AN8 is the step up you make when AN6 is restricting things: main fuel feed on a turbo or supercharged engine, oil cooler feed and return, turbo oil drains and surge tank plumbing all commonly run this size. Stainless is the right call when the tank or reservoir is itself stainless, or when the fitting sits in a wet, salty or heat-soaked area and you want it to still look and seal properly years later. Weld with matching filler, keep heat input controlled so the flare seat stays flat, and thread the mating AN8 hose end on without sealant.