3a thread class right-hand 0.270" thread length flat chamfer head style 2.875" grip length 28 thread quantity per inch passivate surface treated unf thread series
2a thread class right-hand 0.512" thread length flat countersunk head style 40 thread quantity per inch cadmium or zinc screw surface treated unc thread series
2a thread class right-hand 0.472" thread length flat countersunk head style 28 thread quantity per inch cadmium screw surface treated unf thread series
2a thread class right-hand 0.275" thread length flat countersunk head style 36 thread quantity per inch cadmium or zinc screw surface treated unf thread series