At AN20 the hose is stiff and its bend radius is large, so trying to force a right-angle turn with a straight fitting is not realistic — the elbow has to be in the fitting. This 90-degree hose end does that, letting big dry-sump, cooler and fuel lines exit a tank or pump port and immediately head where you need them. The swivelling AN20 nut allows the joint to be made up without winding the hose. Reusable socket-and-nipple construction. Assembly at this size takes real leverage: clamp the socket in soft jaws, lubricate the nipple, and use correctly sized spanners on the final connection.