When that massive storm is sure to shut the road to the resort down, you'd better be prepared to make camp in the parking lot if you're going to get first tracks. The Haglofs Lupus 4F Synthetic Sleeping Bag will keep you warm when you're winter camping with its Tri Fusion synthetic insulation. With a 4F temperature rating, the Lupus will keep you warm when the temperatures duck just below zero, but you'll really be most comfortable around 10F, making this pack ideal for cold, winter environments. Every feature on the bag is designed to yield thermal efficiency with a standard mummy shape and a body hugging hood and foot box. An insulated draft tube and collar prevent heat from being lost throughout the night, while an internal pillow pocket keeps your camp pillow securely in place while you dream of the powder fest to come.