Become a Member

Get access to more than 30 brands, premium video, exclusive content, events, mapping, and more.

Already have an account? Sign In

Become a Member

Get access to more than 30 brands, premium video, exclusive content, events, mapping, and more.

Already have an account? Sign In

Brands

Jacket Reviews

Mammut Aconcagua Light ML Hooded Jacket

The best heat-trapping midlayer of 2021.

Lock Icon

Unlock this article and unwrap savings this holiday season.

Already have an Outside Account? Sign in

Outside+ Logo

Now 30% Off.
$4.99/month $3.49/month*

Get the one subscription to fuel all your adventures.


  • Map your next adventure with our premium GPS apps: Gaia GPS Premium and Trailforks Pro.
  • Read unlimited digital content from 15+ brands, including Outside Magazine, Triathlete, Ski, Trail Runner, and VeloNews.
  • Watch 600+ hours of endurance challenges, cycling and skiing action, and travel documentaries.
  • Learn from the pros with expert-led online courses.
Join Outside+


*Outside memberships are billed annually. You may cancel your membership at anytime, but no refunds will be issued for payments already made. Upon cancellation, you will have access to your membership through the end of your paid year. More Details

Whether we were hiking in chilly conditions or hanging around camp at dusk, the Aconcagua Light was our stretchy second skin. “I loved how soft the ribbed lining is, and it stayed that way even after multiple washes,” says one tester, who threw it on over a sports bra after a breezy 45°F trail run in the Tetons. An 80-denier polyamide/elastane knit outer is lightweight but tough enough to handle brushes against branches and rocks, and the fitted hood has a ponytail hole (feedback was mixed on that feature). Two zippered front hand pockets are roomy enough to fit gloves and a big smartphone. The Aconcagua Light packs down to the size of a cantaloupe.

w’s XS-XXL

When you buy something using the retail links in our stories, we may earn a small commission. We do not accept money for editorial gear reviews. Read more about our policy.