This AN12 90° swivel adapter joins a male flare connection to a female swivel that can be rotated into position, which matters greatly at this size where a large hose has very little tolerance for being twisted into place. It suits high-volume work — surge tank and swirl pot connections, large oil cooler runs, dry-sump plumbing and generous fuel systems — where the line must turn sharply off a component port. Fit the male end first, then clock the swivel and tighten the hose end. Allow room to swing a spanner on both hex flats, as AN12 bodies are bulky and cramped installations can leave nowhere to grip.