2a single mounting facility thread class 0.375" single mounting facility thread length 1.600" overall length 1.600" overall width 32 single mounting facility thread quantity per inch unc single mounting facility thread series
2b thread class right-hand 1.280" overall length 1.280" overall width 40 thread quantity per inch 0.677 in. min cadmium surface treated square shape unc thread series
2b thread class right-hand 1.198" overall length 1.198" overall width 40 thread quantity per inch 0.614 in. min chromate surface treated square shape unc thread series