MS51963 Cup Point Hex Socket Set Screw, Plain and Self Locking, Alloy Steel, Cad Plated, UNC-3A (S/S by NASM51963, 30 SEP 1999). Socket Set Screws come in different types and sizes including: AN565, MS18063, MS18064, MS51021, MS51023, MS51029, MS51031, MS51038, MS51045, MS51963, MS51964, MS51965, MS51966, NAS1081. MS51963C (NOTICE 1), MILITARY STANDARD: SETSCREW-HEXAGON SOCKET, CUP POINT, ALLOY STEEL, CADMIUM PLATED, UNC-3A, PLAIN AND SELF-LOCKING (30 SEP 1999) [SUPERSEDED BY NASM51963].