July 30, 2020 2 min read

Regulate Comfort in Changing Conditions

Polartec® Alpha® was invented for the U.S. Special Forces. They required a superior insulation system for extreme temperature variations without shedding layers during combat. 

Polartec® Alpha® was invented because some things in life happen too fast to layer up or down. The U.S. Special Operations Forces (SOF) can think of a few reasons, and for years there were no options on the market that could meet their specific needs — a breathable, quick-drying and packable insulation for demanding start-stop activities. Polartec Alpha came to be through extensive lab and field testing in extreme environments, including cold weather combat training in Kodiak, Alaska.

Polartec Graphic of Breathable MaterialHow Alpha Insulation works to keep your body dry and your temperature regulated.

Traditional down or synthetic, usually works to keep the wearer warm but traps sweat when you are on the move. However, Alpha uses lofted fibers connected to a sturdy knit-lattice structure, creating a stable layer that allows for more air-permeable fabrics. As the world’s foremost fabric finisher, Polartec was able to figure out how to brush this (nearly lacelike) open knit without ripping it apart. This shape allows airflow, allowing the Alpha to function in a wider range of activities without the need to add or shed layers.

In addition to unprecedented levels of breathability and moisture vapor transport, Polartec Alpha still insulates effectively while wet and offers dramatically faster dry times. This versatility means Alpha can be paired with pretty much any combination of facing or backing fabrics — or no fabric at all (Alpha Direct).

Ambassadors Jordie Karlinsky and Zach Hayes hiking in two of our Active Midlayers, the Women's Alpha Direct Insulator and Men's Alpha Shirt Jacket. Photo by Jordan Curet.

Polartec® Alpha® Direct Insulation takes Alpha's features one step further with enhanced resiliency and durability. Alpha Direct's insulating fibers are uniquely shaped and sized to eliminate the need for a facing fabric. This visible technology offers direct warmth, increased breathability and compressibility, and even faster dry times, while reducing garment weight due to the lack of lining fabric.

What does all this tech talk mean? Base layers, insulation, and outerwear can all be combined in a single garment. This means less gear to carry and less time spent stopping to adjust layers depending on temperature and output. Polartec Alpha offers the most comfort throughout the widest range of temperatures and activity levels, so its uses are boundless.

Walking through snow in Midlayer.

Bryce Gordon staying warm in our Alpha Direct Insulator. Photo by Jordan Curet.

Strafe brought this unique material to life in several of our insulation pieces, as both Alpha and Alpha Direct. Our  ALPHA DIRECT INSULATOR exemplifies the light and fast "put it on keep it on" mantra that Pete Gaston advocates when in the mountains.  The SUNNYSIDE ALPHA ANORAK works equally well as a light midlayer when paired outerwear, or as a stand alone piece on warmer spring missions. The air-permeable Recon Air fabric & lightweight Polartec Alpha insulation will keep you comfortable and dry when you're working hard while retaining critical warmth on chilly mornings in the backcountry

Highly breathable, quick drying, durable and lightweight make Alpha and Alpha Direct the perfect partner for big days in the mountains.

Trail Running in Strafe Midlayers.

Photo by Jordan Curet.

Information Courtesy of Polartec.



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