The Summerlite 32 Degree Down Sleeping Bag is Western Mountaineering's lightest bag with continuous baffles, ideal for backpacking anywhere from nearby lakes to the faraway alpine. This mummy bag achieves a phenomenal light weight through its 850 down insulation, the loftiest down available on the market. Western Mountaineering wrapped up this ultralight insulation with a water resistant ripstop material, which Western Mountaineering claims is the lightest downproof fabric out there. The shell's water resistance helps the insulation retain its loft, and warmth, in moisture riddled environments. Western Mountaineering's critical thought to the smallest details makes the Summerlite a long lasting and very versatile choice. A differential cut places more fabric at the lining to ensure maximum loft inside the bag, and continuous baffles allow you to shift the bag's down toward the top or bottom for more or less warmth. Hook and loop tabs let you pull the hood, draft tube, and draft collar farther or closer to you for customized coverage. Extra convenient features include full length zippers on either side, a waterproofed stuff sack, and a storage sack with a large volume that helps the bag retain its loft overtime.