Pre shaped collar to provide comfort and a tighter seal. Full barrier and back zip for easy on/off.Also allows for a bigger opening for easy entry and exit. Internal Furnace lining with increased oxygen hollow yarn, traps and retains heat more efficiently keeping you warmer longer. Premium lightweight foam core, providing the optimum blend of thermal retention, flexibility and durability. Durable impact welded seam sealing internally on critical stress areas for water tight durability. Pre shaped panels aiding in comfort and maneuverability. Placing the seams in the optimum position to maximize flexibility and comfort. Fused edges providing the perfect beveled edge to help reduce any water entry.