The CAESAR II material database does not contain all of the materials you may find listed in the Codes. We incorporated what we felt were the most commonly used materials. This is why the "Material Database Editor" exists, so you can add additional materials to the database if necessary.

As to the "CAESAR II Material Numbers", they are simply the order in which the materials were added to the database.

ASTM304 is not in the CAESAR II Material Database. If this is a material which you anticipate using frequently, I suggest you add it to the database. If this is a "one time only" issue, simply enter the material data on the piping input spreadsheet.