Didn’t know that Prestone made a dedicated product. Had to add a bit of CHF-202 (and CHF-11S is also compatible) to my daughter’s Volvo when I was in Salt Lake City last summer. Outrageously priced at a local Advance Auto Parts.It's the Prestone Euro formula.
Prestone® European Vehicles Power Steering Fluid - Prestone® Total Protection
Prestone® European Vehicles Power Steering Fluid enhances system life vs. conventional fluid. This synthetic fluid is designed with 2X Anti-Wear System Protection, which means more protection against pump failure, squeals and clogs.prestone.com
This would have been a better choice in that circumstance (a few ounces needed).
Still, I buy CHF-11S by the 5 liter jug for the ABC suspension on both MB. Takes 12-15 liters for a full flush, done every other year. So, I always have a bit with which to top off a Mercedes PS system…