3a thread class right-hand 0.531" thread length flat countersunk head style 32 thread quantity per inch passivate screw surface treated mark head w/letters cn unf thread series
2a thread class right-hand 1.826" thread length flat countersunk head style 24 thread quantity per inch cadmium screw surface treated unf thread series
2a thread class right-hand 1.574" thread length flat countersunk head style 56 thread quantity per inch cadmium screw surface treated unc thread series