M8 X 25mm ~ 8.4mm i/d ~ 25mm o/d ~ 2mm thick. M12 X 40mm ~ 12.5mm i/d ~ 40mm o/d ~ 3mm thick. M10 X 30mm ~ 10.5mm i/d ~ 30mm o/d ~ 2mm thick. M4 x 12mm ~ 4.3mm i/d ~ 12mm o/d ~ 1mm thick. M6 x 18mm ~ 6.4mm i/d ~ 18mm o/d ~ 1.6mm thick.
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