M8 ~ 8.4mm i/d ~ 16mm o/d ~ 2mm thick. M10 ~ 10.5mm i/d ~ 20mm o/d ~ 2mm thick. M4 ~ 4.3mm i/d ~ 9mm o/d ~ 1.5mm thick. M8 X 25mm ~ 8.4mm i/d ~ 25mm o/d ~ 2mm thick. M4 x 12mm ~ 4.3mm i/d ~ 12mm o/d ~ 1mm thick.
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