Conquer cold mountain days with confidence. The X-BIONIC® ENERGY ACCUMULATOR 4.0 PANTS 3/4 MEN regulate body temperature using the 3D Bionic Sphere® System with ThermoSyphon® for optimal sweat management and cooling. Expansion Ribs® ensure insulation and freedom of movement, while Intercooler technology prevents overcooling between exertion periods. This expert baselayer fuels endurance, warmth, and agility throughout winter adventures.