These are a DIN 985. Further details are as follows Nyloc Nut Across the Flats (A/F) - 5.5mm. Nyloc Nut Height - 4mm. Nyloc Nut Across the Flats (A/F) - 7mm. Nyloc Nut Height - 5mm. Nyloc Nut Across the Flats (A/F) - 8mm.
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