The turbo unit itself must be CARB approved (EO number stamped). The unit must be CARB approved for use on a 1994 Porsche Cayman, with specifically your engine configuration. So technically it's one EO number, but the component must be able to fit in with the rest of the emissions system.
More Aftermarket Component Info:
https://www.smogtips.com/aftermarket-performance-parts.cfm