After a long day of steady ascents, you'd like nothing more than to sit back and relax in your sleeping bag, but after about thirty seconds of staring at your tent wall, it gets pretty old. With the Sierra Designs Mobile Mummy 600 Sleeping bag you can enjoy the simple pleasures of your bag while you move about camp. The award winning design of the Mobile Mummy places zipperless ports at the shoulders and foot of the bag, enabling your limbs to move freely when you're ready to go explore. Secure the foot box to the back of the bag so it doesn't drag behind you, and you'll be ready to roll. For warmth, the bag is insulated with a 600 fill hydrophobic down, so it will retain insulating properties if it happens to get wet. When you're ready to hit the hay, the bag still functions as a traditional sleeping bag thanks to a draft free design that puts baffles at the collar, feet, zipper, and armholes. Suitable for three season use, you'll stay comfortable in this bag when temperatures drop to around 27 degrees Fahrenheit.