This straight adapter mates an AN16 37-degree male flare to a 3/4″ NPT male pipe thread. AN16 is a big hose size, used where volume matters far more than pressure: dry sump scavenge, large oil cooler circuits, breather and coolant transfer plumbing, and race-level fuel delivery. Mounting it to a 3/4″ pipe port is a mild reduction, so the NPT end sets the effective bore of the joint. That is often acceptable at a pump or cooler boss that was never tapped larger. Seal the tapered NPT threads with a suitable sealant and assemble the AN flare clean and dry, torquing it firmly rather than crushing the flare face.