COLEMAN Big Bay Sleeping Bag 0 Degree Mummy Fog Cold-weather camping is easy when you have a Coleman Big Bay 0 Degree Mummy Sleeping Bag. From weekend camping trips to stargazing nights in the backyard, this sleeping bag's Coletherm MAX insulation will keep you warm in temps as low as 0 degrees F. Tend to run cold? The semi-sculpted hood and Thermolock draft tube helps to lock in heat so you stay comfortable when the temps drop.