Sleeping Bag Fill & Construction
Added together, it’s all these little details that make a great sleeping bag and push Western Mountaineering over the top! For instance, all of their winter bags with the Full Down Collar are made with Interlocking Double Draft Tubes. When the bag is zipped these large stoutly filled tubes rest side by side rather than on top of each other. That way these Interlocking Draft Tubes retain their full loft without being compressed as the zipper closes. When a bag has a single draft tube it will hang from the top so that the zipper won’t inadvertently be exposed while moving inside the bag. A Dacron stiffening tape is sewn alongside each zipper to prevent or at least minimize zipper snags.
Our Hook and Loop closures are backed with fabric to prevent fraying and are placed on non-integral parts of the bag like the draw cord casing. WM have created a series of icons that represent features found on Western Mountaineering sleeping bags. At a glance you will be able to tell which bags have single or double draft tubes, passive or full down collars, continuous baffles and the type of side block baffle. These icons appear throughout the catalog for each sleeping bag.
These pictures help you understand which type of construction is used on which bag. Sewn threw is easiest, and least expensive, but doesn't allow for full expansion of the down, and the seams produce cold spots. Baffles use netting to separate the chambers and allow for full expansion of the insulation, with no cold spots.