A 90-degree female flare swivel adapter in AN12, the largest option in this family. AN12 lines carry serious volume on big fuel systems, dry sump scavenge circuits and large oil coolers, and hose that size is close to unbendable in a confined space. The elbow provides the turn at the fitting so the hose can run straight into and out of it, preserving flow and taking the strain off the hose ends. The swivel joint lets you torque the 37-degree flare first and orient the outlet afterwards, which is the only practical way to align a heavy line accurately. Confirm both mating components use the AN 37-degree flare seat before ordering.