本SAE航空航天标准（AS）规定了根据AS4716在压盖中使用的实心未切割聚四氟乙烯（PTFE）保持器（支承环）。它们通常用于液压和气动系统部件中，作为防挤压装置，与O型环和其他密封件一起用于静态和动态应用。

This SAE Aerospace Standard (AS) specifies solid, un-cut polytetrafluoroethylene (PTFE) retainers (backup rings) for use in glands in accordance with AS4716. They are usually used in hydraulic and pneumatic system components as anti-extrusion devices in conjunction with O-rings and other seals for static and dynamic applications.