2a thread class right-hand 0.648" thread length fillister head style 28 thread quantity per inch passivate screw surface treated bearing surface to shank hole center 0.670 in. unf thread series
2a thread class right-hand 1.326" thread length flat countersunk head style 48 thread quantity per inch cadmium screw surface treated unf thread series
3a thread class right-hand 0.339" thread length flat countersunk head style 32 thread quantity per inch cadmium screw surface treated unjc thread series