3b 1st end thread class 20 1st end thread quantity per inch knurl finish on section of center outer surface cadmium outside surface treated uns 1st end thread series
Used on viking s-3a aircraft. 3a all ends thread class two safety wire holes 0.047 in. dia in opposite corners of hex anodize surface treated flared w/ center wrenching facility unjf all ends thread series
2a 1st end thread class 20 1st end thread quantity per inch counterbored 0.382 in. to 0.387 in., 0.070 in. to 0.080 in. deep both ends; extra strong uns 1st end thread series
Used on aircraft application. 3a all ends thread class weapon system essential cadmium surface treated flared w/ center wrenching facility unf all ends thread series