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 virgin, unfilled polytetrafluoroethylene (PTFE) in the form of sheet, manufactured by compression molding and sintering. This sheet has been used typically for parts requiring chemical resistance up to 500 °C (260 °C), with better mechanical properties and/or electrical properties than AMS 3667, but usage is not limited to such application.