The Danner USAF TFX is lightweight, comfortable and fast. Sage green leather upper. Lined in waterproof, breathable GORE-TEX for comfort and protection from the elements. The TERRA FORCE X platform gives the boot lightweight, durable traction, heel-to-toe energy transfer and side support to enhance maneuverability. A Fatigue Fighter footbed delivers all-day comfort. Approved for optional wear by the USAF.