M18 / M20 / M22 / M24. M2.5 / M3 / M3.5 / M4 / M5 / M6 / M8 / M10 / M12 / M14 / M16. Material: A4-70 / 316 stainless steel. There are high quality GB96 / DIN9021 larged flat washer.
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