So, we've kept you dry with the base layer, and retained your body heat with some gnarly insulation. However, there are three parts to obtaining functional fusion; the third is to keep out the cold. No SH#$*$ you say... Although, this may sound obvious it is far more difficult than you may expect. It is actually three challenges in one. We conquer each one of these through the use of several unique materials which stop the wind and rain, and allow moisture to "vapor out" through a microporus membrane.