This document has been declared "Stabilized" and will no longer be subjected to periodic reviews for currency. Users are responsible for verifying references and continued suitability or technical requirements. New technology may exist. This specification covers one grade of cast methyl methacrylate plastic in the form of sheet. This sheet has been used typically for fabricated parts, formed or otherwise, requiring dimensional stability, optical clarity, good electrical properties, and excellent outdoor weatherability, but usage is not limited to such applications.