Representing the highest level of performance in Burton's line of functional outerwear, the [ak] line debuted in 1997 as the culmination of a partnership between Burton and W.L. Gore & Associates, the company responsible for developing GORE-TEX fabric. Burton team riders John Jackson and Kimmy Fasani recently paid a visit to Gore's testing facilities in Newark, Delaware, to experience firsthand the rigorous testing that their outerwear undergoes before it's deemed fit for use in the backcountry. Before the garment can be graded worthy of Gore's famous "Guaranteed to Keep You Dry" promise, it must survive the Rain Room, a laboratory environment where the actual velocity of rainfall is reproduced to test waterproofing, as well as the Comfort Chamber, where the material's breathability and warmth are measured against temperatures ranging from 120 degrees Fahrenheit to minus 20. Check out the video overview below.