A13-3

1/2 x 20 unf male fully threaded steel nut, SAE (double) flare, .600” long. Uses 1/2” wrench. American thread master cylinder brake line nut for use with 3/16” o.d. tubing with SAE (double) flare. As the name implies, this is found most often at the master cylinder but is also found at ABS units and other places.