Men's K-Swiss Tubes Comfort 200 Running Shoes Introducing the Tubes Comfort 200, a trainer that features K Swiss' patented Tubes system. The technology provides unmatched comfort and cushioning through individually tuned tube structions that collapse and rebound as you walk. The design also provides incredible flexibility making every stride smooth and efficient. Smaller, more rigid tubes on the inside area of the heel provide extra medial support to reduce pronation. A lightweight mesh upper provides additional coolness and breathability to make this shoe one of the most comfortable trainers you will ever experience.