An inverted seat adapter that mates an AN8 37-degree flare to a 1/2 x 20 inverted flare thread. Inverted flare is the seat OEMs use on hard lines for brakes, clutch circuits and fuel plumbing, and it is not interchangeable with AN – the seat angle and thread are different, so an adapter is the only correct way to join the two. That makes this the part you want when you are converting a factory hard-line port over to braided AN8 hose without cutting or re-flaring the original line. Both ends seal metal to metal on their seats, so no tape or sealant is needed on either side. Fit it dry, seat it squarely to avoid cross-threading the fine 20 TPI thread, and nip it up firmly rather than heavily.