X-Bionic Energizer MK2 Running Tights - SS17 Two-Step Front 3D-BionicSphere System - Ensures optimal grip and climate comfort. ExpansionKnee - Provide insulation by storing warm air inside. 3D-BionicSphere System at the coccyx - Effectively protects against chafing and irritation. AirConditioningSpot - Avoids sweat accumulating at the back of the knee. Technical Composition - 70 % SkinNODOR 22 % Polyamide 5 % Elastane 3 % Mythlan