We added reinfoced 300 denier poly-twill material on high-wear areas like the knees, ankles, and seat for added durability from use and abuse in the field. MATERIALS - Waterproof/windproof/breathable Refuge HS with HyperShield 2.0 Technology, Reinforced knees, seat, and wear areas with laminated 300 denier fabric, 180g polyester insulation, Taped seams.