2a 2nd end thread class 20 all ends thread quantity per inch nha power unit, front, nsn 2320-01-417-3180 rigid, threaded internal unf all ends thread series
Used on f-16 and f-18 aircraft. 3b 1st end thread class 24 1st end thread quantity per inch normal operating range is 3000 psi; higher psi version available, nsn 4730-00-283-6397 (8000 psi) dynatube unjs 1st end thread series