Perspex Cast acrylic sheet tolerances is +/- 10 % plus 0.4mm ( 3mm cast sheet could vary from 2.3mm to 3.70mm and 5mm cast sheet could vary from 4.1mm to 5.9mm). PERSPEX APPROVED FABRICATORS. EXCEPT ON 50mm DIA WHICH IS 10mm ALL ROUND (70mm OD).
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