Used on c-17 aircraft. 3a all ends thread class 12 all ends thread quantity per inch union tube-flareles forced expan nipple has .19 thicknes tear shaped center lobe instead of wrenching facility, also includes anodized washer & jam nut lubricant dry film surface treated flareless (tube) unj all ends thread series
3a 2nd end thread class adapter, flanged, welded-bulkhead, reducer, permaswage to male flareless passivate flange surface treated unjf 2nd end thread series