M14; internal Ø 14.2mm; external Ø 21.1mm; thickness 3mm. M16; internal Ø 16.2mm; external Ø 24.4mm; thickness 3.5mm. M8; internal Ø 8.1mm; external Ø 12.7mm; thickness 2mm. M12; internal Ø 12.2mm; external Ø 18mm; thickness 2.5mm.
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