Applicable:M4,M5,M6,M8,M10,M12,M14,M16,M18,M20,M24,M27,M30. e.g 21x13xM14 (inner hole width of 21mm total height of 13mm applicable nut M14). Made of polyethylene (PE), non-polluting, slightly elastic, with good low temperature resistance (use temperature up to -100°C ~ 70°C).
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