This SAE Aerospace Information Report (AIR) summarizes the materials referenced in specifications for components used in USA fluid systems and, where available, the equivalent materials of France, Germany, United Kingdom, and USSR. (See Figures 1 through 8.) The data in this document compares ISO and NATO materials equivalents to AIR1564, Materials for Fluid Systems Components and Their International Equivalents. The equivalent material information was obtained from periodicals, books, and data supplied by individual contributors. No attempt has been made to obtain samples of the materials or conduct physical and chemical analyses to determine if they are equivalent. Anyone using this AIR, therefore, is cautioned to verify for themselves the interchangeability of the specific materials. Additional contributions of missing or supplemental data should be directed to SAE marked for the attention of Committee G-3.