Designed to reduce fatigue during long days walking, Mammut\'s T Aenergy High GTX Boots use their patented Rolling Chassis concept which better protects the foot, improves forefoot flex and control from step to step.The Vibram outsoles have deep lugs for outstanding grip and lasting surefootedness across rough ground. All of this comes in a lightweight boot, made from durable yet lightweight, comfortable suede / nylon upper and GORE-TEX waterproof footwear membrane, which will ensure your feet are happier at the end of a mammoth trek.GORE-TEX waterproof, breathable linerBase Fit - sliding webbing transfers power from lacing area to the solesHybrid shell - tough outer and supple innerMemory Foam - individual fit3 Zone Lacing - secure fit all the way down the tongueRolling Concept - stimulates the foot\'s natural roll to reduce the chance of injuryVibram Scale Sole - modelled after the scales of an anteaterFlex index: A7Colour: Blue