2a thread class right-hand 0.514" thread length flat countersunk head style 18 thread quantity per inch passivate screw surface treated unc thread series
3a thread class right-hand 0.156" thread length headless (setscrew) head style 64 thread quantity per inch navy special project passivate surface treated unc thread series
2a thread class right-hand 0.688" thread length fillister head style 0.047" hole diameter 32 thread quantity per inch cadmium screw surface treated unc thread series