2a thread class right-hand 0.540" thread length flat chamfer head style 28 thread quantity per inch slot in point 0.06 in. w by 0.05 in. dp passivate surface treated unf thread series
2a thread class right-hand 0.187" thread length flat chamfer head style 40 thread quantity per inch navy special project passivate surface treated unc thread series
3a thread class right-hand 0.614" thread length headless (setscrew) head style 28 thread quantity per inch passivate surface treated unjf thread series