Used on guardrail(systems 1-4); fire pumps. 2a thread class right-hand 0.938" thread length flat countersunk head style 32 thread quantity per inch unf thread series
3a thread class right-hand 0.656" thread length flat countersunk head style 20 thread quantity per inch passivate screw surface treated unf thread series
2a thread class right-hand 0.580" thread length flat countersunk head style 40 thread quantity per inch cadmium or chromate surface treated unc thread series
2a thread class right-hand 0.530" thread length hexagon head style 20 thread quantity per inch cadmium surface treated concentric hole unthreaded unf thread series
3a thread class right-hand 0.656" thread length oval countersunk head style 20 thread quantity per inch passivate screw surface treated unf thread series
2a thread class right-hand 0.210" thread length fillister head style 0.047" hole diameter 32 thread quantity per inch passivate surface treated unc thread series