A male-to-male reducer with AN6 on one end and AN5 on the other, both using the standard 37-degree AN flare seat. AN5 is an in-between size that appears on certain specialist and OE components, and when you meet one it usually needs to join a system otherwise built in AN6. This fitting makes that connection cleanly instead of forcing a compromise on line size. Both ends are male, so they mate to female swivel hose ends or female couplers. Confirm the port really is AN5 before ordering, as it is easily mistaken for AN4 or AN6. Tighten to a firm seat on the flare and leave sealant off entirely.