The internal design includes a water-trapping feature keeping condensate away from the point-of-use allowing drainage toward the most convenient low point of the system.
The Outlet / Reducing Tee Fitting is an alternative to the traditional swan neck and goose neck (up and over) take-off points, and has proven itself as a fast and low-cost solution.
It prevents water from dropping out of the main piping loop into the drop line. All systems should be install with a slight gradient to allow moisture to collect at one point in the system. This point should be fitted with a drop line and terminated with a condensate drain.