Polartec Alpha: Insulation for Active Pursuits
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Down is the warmest insulation. In fact, when
you’re hiking or skinning, it can be too warm. Same with Primaloft. It’s
fantastic when you reach the summit, when you’re belaying your partner, or
riding a lift, but get your heart rate up, and you’ll probably start to get sweaty.
That’s why Polartec invented Alpha.
Unlike down and existing synthetic insulation
batting, Polartec Alpha is a highly stable layer of synthetic fibers that lets manufacturers
use more open and breathable fabrics on the outer and inner layers of puffy garments. Classic puffies require down-proof fabrics inside and out so feathers don’t poke
through, or they need high-density woven layers. Both create a vapor barrier, trapping moisture inside the garment during activity.
Polartec Alpha allows more air exchange in an insulating garment than ever before, for breathability and comfort when you’re generating heat. In addition to higher breathability than any other insulation because
of the fabrics that manufacturers can use with it, Polartec Alpha stays
warm when wet with faster dry times than other insulating layers. Highly
compressible and feather light, it also provides some wind resistance.
Polartec Alpha was developed for U.S. Special Operations Forces (SOF). In
testing by SOF, Alpha received the highest results of any Polartec product ever
evaluated by the team.
“Polartec Alpha is a natural compliment to
our existing layering system fabrics. It will function as outerwear or as an
ideal mid layer. It packs small and can quickly recover from something as
catastrophic as getting completely soaked while in the field,” said Allon
Cohne, Polartec's director of marketing. “This is a never-let-you-down
active warmth product that will replace other layers, lighten the load, and
increase comfort in the field for outdoor enthusiasts.”
It’s not as warm as garments that bear a vague
resemblance to your sleeping bag, but it’s a highly functional layer that so
far has kept testers warm without overheating them, even when they were running
Look for Polartec Alpha in clothing from 66º
North, Eddie Bauer, Eider, Mammut, Marmot, Montane, Mountain Equipment, Rab,
Ternua, Terry Bicycle, The North Face, Trangoworld, Vaude, and Westcomb in fall
Rab’s Strata Hoodie, pictured
above, has a stretchy Pertex Microlight 20D outer shell with
comfort stretch, 80 grams
of Polartec Alpha, and body-mapped woven nylon and poly-mesh inner layer. The hood
fits over or under a helmet, and the chest pocket doubles as an integrated
stuff sack. Available September 2013, 15oz (men’s
L), $225; us.rab.uk.com.