The thread size of 4AN is 7/16-20 UNF. The AN side of the flare is sealed with a 37 degree angle and the NPT thread side is sealed with a 60 degree tapered threads.
VehiMata 4AN Male Flare to 3/8 NPT Straight Pipe Fitting 3/8, Black
Yellow Jacket 19173 5/16" Female Quick Couplers x 1/4" Male Flare
Yellow Jacket 19165 1/2" Acme Female x 1/4" Male Flare Quick Coupler
TBI/Vortec 87-98 Truck 6AN Male Flare Supply M16-1.5 to Oring, Natural
