This specification has been declared "CANCELLED" by the Aerospace Materials Division, SAE, as of December 2010 and has been superseded by MIL-PRF-6855. The requirements of the latest issue of MIL-PRF-6855 shall be fulfilled whenever reference is made to the cancelled AM-R-6855. By this action, this document will remain listed in the Numercial Section of the Index of Aerospace Matreial Specifications, noting that it has been superseded by MIL-PRF-6855.Military reinsated military specification. AMS cancelled to avoid confusion with military document.This specification covers the requirements for low temperature resistant sheets, strips, and molded or extruded shapes fabricated from synthetic rubbers.