Stainless steel gb nut standard size is M1.6-M64.
1, stainless steel gb nuts include: hex nuts (GB6170/DIN934), thin nuts (GB6172/DIN439), heavy nuts (metric, US), nylon lock nuts (DIN985-DIN982 thick type), all metal lock nuts (DIN980M), cover nuts (DIN1587).
Flange nuts (GB6177/DIN6923), nylon lock nuts (DIN6926), flange nuts (DIN928), hexagon welding nuts (DIN929), butterfly caps (GB62, DIN315, US), K caps, etc.
2, alloy steel gb nut standard size is 5/16-4".
Alloy steel gb nuts include: Hex nuts (GB6170/DIN934, GB6175), flange nuts (GB6177/DIN6923) round nuts (GB812), small round nuts (GB810), SQUARE nuts, HEX nuts (ANSI/ASME B18.2.2), heavy nuts (metric, US).