3a thread class right-hand 0.373" thread length flat countersunk head style 24 thread quantity per inch passivate screw surface treated unc thread series
2a thread class right-hand 0.542" thread length flat countersunk head style 24 thread quantity per inch passivate screw surface treated unf thread series
3a thread class right-hand 0.750" thread length flat fillister head style 32 thread quantity per inch passivate screw surface treated unjc thread series