本规范涵盖模制棒、管和型材形式的未填充聚四氟乙烯（PTFE）。本规范不适用于平行于施加成型压力方向的尺寸超过12英寸（305毫米）的产品、直径小于0.750英寸（19.05毫米）的杆件以及壁厚小于0.500英寸（12.70毫米）的管件。这些模塑件通常用于套管和绝缘体等零件，要求化学惰性和高达500 mDC（260 mDF）的良好机械和电气性能，但用途不限于此类应用。对于轴承、密封件和支承环等不需要介电性能的应用，建议使用AMS 3678/1 A级。

This specification covers virgin, unfilled, polytetrafluoroethylene (PTFE) in the form of molded rods, tubes, and shapes. This specification does not apply to product over 12 inches (305 mm) in dimension parallel to the direction of applied molding pressure, rods under 0.750 inch (19.05 mm) in diameter, and tubes having wall thickness under 0.500 inch (12.70 mm).These moldings have been used typically for parts such as, bushings and insulators, requiring chemical inertness and good mechanical and electrical properties up to 500 \mDC (260 \mDF), but usage is not limited to such applications. For applications such as bearins, seals, and back-up rings that do not require dielectric properties it is recommended to use AMS 3678/1 Grade A.