These are tapped oversized threads to allow for galvanised layer on male thread. Available in M6, M8, M10, M12, M16. M16 2.0 10.5 16 24 26.75. M8 1.25 5.5 8 13 14.38. M12 1.75 8 12 19 21.1. M10 1.5 6.5 10 17 18.9.
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