This AN4 tee provides male 37° flares on the straight run and a female swivel on the branch port. AN4 covers turbo oil feeds, brake and clutch lines, boost reference plumbing and gauge senders, and a tee at this size is typically used to pick up a sender or gauge from a live line, or to split a feed between two consumers. The swivel branch allows the hose to be clocked after tightening, which matters in the cramped, hot spaces these lines usually occupy. Keep the branch supported and route it away from exhaust and moving components before final assembly.