M16; O/D 30.0mm / I/D 16.9mm / Thickness 3.0mm. M8; O/D 16mm / I/D 8.5mm / Thickness 1.6mm. M12; O/D 24mm / I/D 13.0mm / Thickness 2.5mm. M10; O/D 20mm / I/D 10.5mm / Thickness 2.0mm. M4; O/D 9mm / I/D 4.4mm / Thickness 0.8mm.
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