2a thread class right-hand 0.639" thread length flat countersunk head style 18 thread quantity per inch cadmium or zinc surface treated unc thread series
2a thread class right-hand 0.188" thread length hexagon head style 40 thread quantity per inch navy special project cadmium surface treated unf thread series
2a thread class right-hand 0.559" thread length pan head style 40 thread quantity per inch lock washer rockwell c scale 45 to 53 cadmium surface treated unc thread series
3a thread class right-hand 0.625" thread length flat countersunk head style 32 thread quantity per inch cadmium fastener surface treated unjf thread series
3a thread class right-hand 0.812" thread length flat countersunk head style 32 thread quantity per inch cadmium fastener surface treated unjf thread series