Super Spiral-Stretch System (US.Patent No.7,900,301)
Offering sweet dreams with superior stretch and comfort for all shapes and sizes

Montbell has adapted a classic tailor’s trick by integrating a woven fabric “cut on the bias”. By orienting the fabric’s warp and weft threads at 45 degrees to most major seam lines the sleeping bag becomes more fluid or elastic in nature. Additionally, to create an even more comfortable system we utilize an elastic stitch technique to create small “gathers” in the quilting. By combining the strategic seam orientation and the elasticized gathers we offer unrivaled fit and comfort.

Our sewing lines utilize an elasticized thread to create gathers in the quilting that draw insulation closer to your body and minimize drafty dead spaces.




The greatest benefit to using elasticized sewing lines would be the “stretchy” nature of the baffles. These flexible baffles allow our sleeping bags to move with you as you change positions throughout the night.

Fill power (or loftiness) refers to the volume in cubic inches that 1 ounce of down will displace. The higher the fill power, the less down is needed to achieve a given thermal profile. All other things being equal (fabric, construction method, and fill amount), a product made with high fill power down (900) is lighter and more compressible than an equally warm one made with lower quality down (550).

An elite water-repellent technology, POLKATEX® DWR protects insulation from light moisture and helps maintain warmth.

At Montbell, we source down from both the European and Asian markets to satisfy a variety of characteristics (supply/availability, low cost, consistent quality, humane practices, etc.) and maintain our lofty standards. Every season we seek to balance the superior quality for which we are known and the lowest possible raw materials cost. We change down sourcing companies frequently to insure that our customers have access to superior products at the lowest price possible. In the course of these efforts, Montbell never purchases down from operations that practice “live-plucking” methods. We only utilize down plumes and feathers collected as a by-product of water fowl raised to meet the demands of the food industry.

We will continue to look for sources of down that maximize value to our customers and allow Montbell products to perform at the highest level.