Used on aircraft model c-130. 3a thread class right-hand 0.454" thread length hexagon head style 2.490" grip length 24 thread quantity per inch cadmium surface treated unjf thread series
3a thread class right-hand 0.298" thread length flat countersunk head style 0.302" grip length 32 thread quantity per inch cadmium surface treated unjf thread series
2a thread class right-hand 0.260" thread length flat chamfer head style 32 thread quantity per inch navy special project passivate surface treated unc thread series