F5 fabrics are specially designed to provide not only superior moisture management, but also to enhance the wearer's comfort. The specially-engineered Coolmax fibers used in F5 fabrics provide enhanced breathability (called "air permeability" by the techies) that differentiate F5 from standard powernet fabrics, which use standard fibers.

Air permeability is just one of our key performance tests that fabrics must pass before they can be sold as "F5". And, remember, that all of the benefits of Coolmax®-certified F5 fabrics are permanently built right into the fiber, requiring no chemical treatments like those other wicking powernet fabrics.