2a thread class right-hand 1.313" thread length flat countersunk undercut head style 32 thread quantity per inch zinc screw surface treated unc thread series
2a thread class right-hand 1.097" thread length pan head style 40 thread quantity per inch navy special project passivate screw surface treated unc thread series
3a thread class right-hand 1.688" thread length flat countersunk head style 56 thread quantity per inch navy special project cadmium screw surface treated unjc thread series
3a thread class right-hand 0.152" thread length pan head style 56 thread quantity per inch navy special project passivate screw surface treated unjc thread series
3a thread class right-hand 1.650" thread length flat countersunk head style 20 thread quantity per inch cadmium screw surface treated unjf thread series
3a thread class right-hand 3.186" thread length flat countersunk head style 20 thread quantity per inch cadmium screw surface treated unjf thread series