Most of the time, with exception of the gaskets of course, all the components in the spec are the same material. Rather than create tons of the same components in the catalogs for the different materials, or from having to go through the material section in every spec and manually inputting the material for every component, it would be so much easier if you could put a global material for the spec and have a check box in the components to use the global material or not. In most cases it would be the global material, but things like gaskets would not be.