3b thread class right-hand 20 thread quantity per inch max surface finish, all surfaces 125 microinch aa, countersink id T0 0.812 in. dia on each side cadmium or passivate surface treated
3b thread class right-hand 20 thread quantity per inch two drilled lockwire holes in hex 180 deg apart, 0.046 in. dia holes, 0.625 in. c to c of holes anodize surface treated