Determined to reduce fatigue when you\'re out traversing the mountain side or trekking across the toughest trails, Mammut have created the essential underfoot supports. The Mammut Men\'s T Aenergy Trail GORE-TEX Boots feature Mammut\'s patented Rolling Chassis concept which works to better protect the feet and improve forefoot flex.Elastic GORE-TEX tongue constructionBase Fit -  sliding webbing transfers power from lacing area to the solesHybrid shell - tough outer and supple innerMemo 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: grey/black