With the weather steadily growing colder, an outdoorsman’s fancies turn to insulated, warm gear to counter the impending frigid months. Soon, outdoor retailers will heavily feature Gore-Tex boots, thermal base layers, and down insulated sleeping bags. Big Agnes, a company well-known in the outdoors world, recently released the Bellyache Mountain SL, a sleeping bag that will have cold weather campers smiling this season.

The most prominent feature of the Bellyache sleeping bag is its water repellant technology. Other than a durable water-reistant ripstop nylon shell, the down insulation within the bag actually employs technology that repels water at that level by applying a water-repelling polymer to the down itself. This means that the sleeping bag remains dry, maintains insulation, and holds its shape even in the wettest conditions. In fact, the sleeping bag’s water repellant down is so effective at repelling water that it actually floats on water. Furthermore, the down insulation is separated by vertical barriers that keep it from shifting or bunching up in the wrong places. This helps ensure fully effective water resistance throughout the bag.

Internally, the Bellyache features a soft, nylon taffeta lining that is incredibly breathable. There’s also a draft tube behind the zipper that prevents cold air from entering while keeping hot air from escaping. Also, handy interior fabric loops help stabilize a sleeping bag liner, should you choose to purchase one for your outings.

The Bellyache impresses from the get-go, but it also excels on paper. It possesses a 17-degrees Fahrenheit temperature rating (that’s -8 degrees Celsius), filled with 700-fill duck down, and weighs in at just over 2 pounds. The bag is also available in two different lengths that cater to varying heights. The Regular model ($299.95) fits adults up to 70 inches while the Long model ($319.95) accommodates up to 78 inches, and both are very affordable.

Any outdoorsman will tell attest to the importance of a quality, reliable sleeping bag, especially during the colder months when a sleeping bag is all that protects you from the sometimes freezing temperatures that nature throws at you. The Bellyache Mountain SL bag from Big Agnes was created to be the only line of defense you’ll need against snow, rain, and frigid climates this winter, due to its utilization of water-repellant, insulating duck down. If you’re an avid cold weather camper or are planning on embarking on colder treks, the Bellyache is worth a look the next time you hit the store.