3a thread class right-hand 0.995" thread length spline extended washer head style 18 thread quantity per inch cadmium surface treated unc thread series
Used on pacer special. 3a thread class right-hand 0.573" thread length flat keyed head style 12 thread quantity per inch hhole in head unjf thread series
3a thread class right-hand 0.425" thread length dished hexagon head style 28 thread quantity per inch passivate headpassivate bearing surface of headchromium grippassivate threads surface treated unjf thread series