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
0.250" hole diameter 0.374" outside diameter 0.020" material thickness navy special project washer contains two additional keys, 0.125" wide, located perpendicular to the larger keys key