If it's reliability you're looking for, the Trestles is your bag. This full-featured, 15° wonder keeps you warm regardless of the conditions. When you can't leave anything to chance, take comfort in knowing that the Trestles' Spirafil, a unique blend of polyester fibers to maximize warmth, loft and compressability, will keep you warm even through the cold and wet. Once you factor in all the features the Trestles brings to the table, it's a wonder how Marmot can let these go for this price. Made with Wave Construction, a shingle construction allowing for more insulation to cover dead spots and minimize heat loss. If you're looking for something that Marmot forgot in this bag, you're better off looking somewhere else. The Trestles features dual zippers, an insulated collar with easy access cord and "Feely" draw cords for simple adjustments, a trapezoidal foot box for plenty of foot room, a snagless draw cord and zipper guards, two way zipper sliders and a stash pocket for midnight snacks. What good is that fancy $500 ultra-light down bag when it gets wet? Sleep tight (and warm!) knowing that you won't be freezing your tush off when the wet and rain get the best of things.