Used on air force sub-scale aerial target (afsat). 3a thread class right-hand 0.500" thread length button head style 32 thread quantity per inch alloy steel button-head socket cap screw oxide surface treated unf thread series
3a thread class right-hand 0.320" thread length dished hexagon head style 0.046" hole diameter 32 thread quantity per inch cadmium surface treated unjf thread series
3a thread class right-hand 0.500" thread length flat countersunk head style 28 thread quantity per inch navy special project passivate surface treated unf thread series