8.500" overall length 3.375" overall width 20 single mounting facility thread quantity per inch tap, circuit selector unc single mounting facility thread series
2b single mounting facility thread class 12.625" overall length 2.812" overall width 24 single mounting facility thread quantity per inch 8 dummy terminals on front of sect 25, shaft is square type tap, circuit selector unc single mounting facility thread series
2a single mounting facility thread class 0.375" single mounting facility thread length 2.742" overall length 1.406" overall width circular wafer, bushing mount unef single mounting facility thread series