MONTANE Fireball Footie - SS17 Pertex outer, Primaloft Insulation Pertex Quantum - Lightweight, 100% windproof Rip Stop Outer - Ensures the bootie remains highly durable. DWR Treated - Prevents water from protruding through the exterior (Durable Water Repellent). 40g Primaloft Gold Insulation - Warm, packable and extremely soft drying. Microfleeced Lining - Warm and sweat wicking.