A male-to-male reducer with an AN5 flare on one end and AN4 on the other, both to the standard 37-degree AN form. AN5 sits between the far more common AN4 and AN6 sizes and turns up on particular OE and specialist components, which is exactly when a reducer like this becomes hard to do without. It lets an AN5 port connect to standard AN4 plumbing without compromise. Both ends are male, so pair with female swivel hose ends or female adaptors. Because AN5 is uncommon, measure carefully before ordering rather than assuming a port is AN4 or AN6. Seat the flare firmly and use no thread sealant.