We looked to the world of ski mountaineering racing, where the competitors
obsess over weight even more than we cyclists do, yet their insulation is a matter
of survival, not merely comfort. And with ski mountaineering being an insanely
aerobic sport, breathability is paramount.
The construction of this jacket is similar to that of an insulated alpine shell, with
an insulation layer sandwiched between woven inner and outer layers. Unlike
most mountain jackets, though, the woven shell isn???¨º?¨¨t completely windproof;
instead, we???¨º?¨¨ve left a small amount of permeability. The small amount of air that
gets into the jacket picks up the moisture and evaporates it more efficiently than
any membrane fabric available. The middle layer is a puffy insulation layer that we
make in polypropylene partly because it???¨º?¨¨s insanely light (specific gravity 0.6g) but
also because it won???¨º?¨¨t pick up moisture from either sweat or rain.
These limited-stretch fabrics require a new cut, so this piece fits slightly looser
than your race jacket. If your winter goals are new Strava PRs rather than winning
races in the spring and summer, you???¨º?¨¨re better served by the Alpha Light Jacket or
a Perfetto. But if your goals involve a real rather than virtual finish line, this jacket
will make your winter riding better.

PRODUCT FETURE:

3-layer insulated construction with engineered air permeability
gives our best combination of warmth, breathability and light
weight
Japanese-made air-permeable woven-textured nylon outer shell
with water-repellent finish
Polypropylene synthetic down insulation layer provides warmth
while allowing full breathability without any water absorption
Pliss??¡§?| stretch panels on sides, elbows and wrists allow for
close-to-body fit yet with full freedom of movement
3 rear pockets with reflective gusset at bottom
Inner waist closure allows you to block out drafts (closed) or
allow extra breathability (open

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