3a nut thread thread class right-hand nut thread 0.562" nut thread thread length 1.597" overall length 18 stud thread thread quantity per inch no.9 stamped on large end to indicate 0.009 in.oversize pitch dia cadmium surface treated stepped unc stud thread thread series
2a nut thread thread class right-hand nut thread 0.250" nut thread thread length 1.875" overall length 32 stud thread thread quantity per inch slot in stud end 0.040 in. wide by 0.050 in. deep passivate surface treated stepped unf nut thread thread series