2a thread class right-hand 0.850" overall length 1.438" overall width 18 thread quantity per inch cadmium surface treated box/wall mount external thread unef thread series
2a thread class right-hand 0.526" overall length 0.686" overall width 28 thread quantity per inch silver surface treated box/wall mount external thread unef thread series
2a thread class right-hand 0.438" overall length 0.750" overall width 20 thread quantity per inch silver surface treated box/wall mount external thread unf thread series
2b thread class right-hand 1.229" overall length 1.157" overall width 56 thread quantity per inch anodize surface treated rectangular, open back w/end clamp unc thread series