This is the extended-body version of the 90-degree AN4 swivel hose end. The longer fitting body pushes the elbow further away from the port before the hose turns, which is what you want when the mating fitting sits in a recess, behind a raised boss, or close to a casting or bracket that a standard-length 90 would clash with. The extra reach also gives more spanner access on tight installations. It keeps the same swivelling AN4 nut, so the joint can be tightened without twisting the hose, and the same reusable socket-and-nipple assembly for braided hose. Check the added length still fits your available space.