Connected two one-way inline valves to "T" that goes into back of PP205si.
Argon is fed into one side and Compressed Air is fed into other side.
Selecting between Argon vs. Compressed Air is done by turning Off Argon and turning On Air -or- turning On Argon and turning Off Air.
When not in use, both Argon and Air are turned off.
Compressed Air normally comes in to 1/4 Quick Disconnect on Pre Air pressure regulator (set to 90psi) after it passes through two Descant filters and Micro filter.
For use in other areas, an adapter hose with one Descant filter and Micro filter are used.
After reading where people have had Descant material get past Descant filter and into their Plasma cutters, put Micro filters after Descant filter to catch any Descant.