Sleeping bags to play a role in warmth, need to rely on the internal filling to form insulation to block the outside cold air, so fluffy down is the preferred material, Western Mountaineering from the United States is famous for high-end down materials in the outdoor circle, the top European goose down with a fluffiness of 850, the formation of a larger insulation space, so the warmth is stronger.
 
In addition to the high-end of the down material, the fabric of Western Mountaineering is also excellent, MicroLite XP™ material, which mainly relies on the combination of high thread count and dense yarn to improve water and wind resistance, unlike other brands that use coated or laminated materials, but has high breathability. In addition, Western Mountaineering also has a very detailed division of the pile structure of the sleeping bag, using a variety of vertical lining structures, among which ninety percent of the products are equipped with three-dimensional down filling baffles on the chest and neck to block the convection of cold and warm air.
 
The diversity of Western Mountaineering sleeping bags is also unparalleled, with four series of ExtermeLite, Microfiber, Gore Winstopper, and Gore Winstopper Expedition from low to high intensity, and there are more than a dozen products to choose from under each series.
 
The ExtermeLite series focuses on lightweight down sleeping bags, which reduce the internal volume and weight of the sleeping bag by cutting and filling down through reasonable partitions, and the compressed volume is between 5-8 liters, which is more convenient to carry, but it is mostly an envelope without a hood, and some styles also need to be used with a sleeping pad, so it is more suitable for hiking, camping and self-driving and other more common environments, with a price of between $300-400.
 
The Microfiber series is basically mummy-style, with enhanced thermal performance, comfortable low temperature at about -20~-10, using the main MicroLite XP™ material fabric, with a chest collar wind baffle, and the side zipper is also blocked by the side wall, suitable for spring snow camping and hiking along the river. The Puma is the largest pile in the series, at 1020g, and sells for a relatively high price of around $800.
 
If you're hiking in the winter or camping in extreme weather, the Gore Winstopper and Gore Winstopper Expedition collections are perfect for each with a down filling capacity of around 1000g, a huge V-shaped side baffle and horizontal baffle across the chest, and a sealing ring cut that retains warm air to cope with the changing weather temperatures of the high-altitude mountains. Sleeping bags vary by temperature scale and range in price from $700 to $1000.
 
If you want to buy high-quality down sleeping bags, you need to spend some energy to buy them by yourself, which is suitable for people who want to climb snowy mountains and have high requirements for warm performance.