M8 - 8mm - Thread pitch 1.25mm - Spanner size 13mm. M4 - 4mm - Thread pitch 0.7mm - Spanner size 7.0mm. M6 - 6mm - Thread pitch 1.0mm - Spanner size 10.0mm. M5 - 5mm - Thread pitch 0.8mm - Spanner size 8.0mm.
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