50mm - 4mm Thickness Outer size: 27.5mm x 18mm. Inner size: 40mm x 29mm. Inner size: 50.5mm x 27.5mm. Outer size: 60mm x 39mm. 50mm - 5mm Thickness Inner size: 38.5mm x 24.5mm. Outer size: 48.5mm x 36mm.
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