Choice of M4, M5, M6, M8 & M10 internal threads. Required hole sizes; M4; 5.6mm - 6mm hole M5; 7.5mm - 7.9mm hole M6; 8.7mm - 9.1mm hole M8; 11.1mm - 11.5mm hole M10; 12.7mm - 13.1mm hole. Installed by simply screwing into a suitable size hole.
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