Used on valve ball. 3a thread class 2.500" thread length 8 thread quantity per inch screw, cap, socket head, self locking (requested name) unrc thread series
3a thread class right-hand 0.375" thread length hexagon head style 1.686" grip length 20 thread quantity per inch passivate surface treated unjf thread series
3a thread class right-hand 0.370" thread length hexagon head style 1.125" grip length 28 thread quantity per inch ball, cres qq-s-763, type 440c; plunger passivate surface treated unjf thread series
2a thread class right-hand 1.480" thread length hexagon head style 20 thread quantity per inch undercut in shoulder length 0.095 in. nom., dia. 0.462 in. nom., extending 0.200 in. from bearing surface of head cadmium surface treated unf thread series