"Simplex 1" and "Simplex 2" are not standard terms in any specific field. They could potentially refer to different things depending on the context.

To help me understand what you're asking about, could you please provide more information? For example:

* What is the context? Are you referring to a specific product, software, or process?

* Where did you encounter these terms?

With more information, I can provide a more accurate and helpful answer.