This steel brake adapter has a female 10x1.25mm DIN bubble flare (concave) port on one end and a 3AN male (3/8-24, 37° convex) on the other end. This part has a large enough hex (9/16") to be used with a crush washer (sold separately) when sealing the 3AN side against a flat faced port. This adapter also has a groove to accept our Retaining Clip (Part No. 3607-001, sold separately) when used as a bulkhead fitting. Sold individually.