Ankle Bone Support System (ABSS) which moulds to the heel without pressure Calf height Full grain leather Waterproof and breathable Goretex upper Vibram sole with full rand.<br><br> Crispi Boots use a technology known as the A.B.S.S (Ankle Bone Support System) which revolutionises the comfort and protection offered in this area. The system also uses innovative materials to cradle the rear section of the foot offering superb comfort over rough terrain.