2a thread class right-hand 0.215" thread length pan head style 32 thread quantity per inch passivate screw surface treated altered NAS1635-08-10 unc thread series
2a thread class right-hand 0.130" thread length fillister head style 56 thread quantity per inch navy special project oxide surface treated unc thread series
3a thread class right-hand 0.625" thread length flat chamfer head style 0.047" hole diameter 24 thread quantity per inch passivate surface treated unrc thread series
3a thread class right-hand 0.750" thread length flat chamfer head style 0.036" hole diameter 32 thread quantity per inch passivate surface treated unrc thread series