With improvements in outdoor tech, ultralight products keep getting lighter and more functional. Take Patagonias newest Nano-Air midlayers as an example. First, the brand had Nano Air (the original), which featured 60 g of FullRange insulation.

　　Then came Nano-Air Light, with 40 g of insulation to boost breathability. Now, its launched the Nano-Air Ultralight family — the lightest addition yet with just 20 g of FullRange Insulation.

　　To put that in perspective, the insulation in Patagonias Nano-Air Ultralight line weighs the same as just five sugar packets or four U.S. nickels.

　　The Nano-Air Ultralight Full-Zip Hoody ($250) and Pullover ($200) are also compressible, stretchy, and water-resistant. Patagonia claims this lighter insulation midlayer will keep adventurers dry and protected from the elements without overheating during high-output activities.

　　Nano-Air Ultralight: Exceptional Air Permeability Stretch

　　Close-up on the hood of a Patagonia Nano-Air Ultralight Hoody; (photo/Patagonia) Patagonia describes its Nano-Air Jacket collection as having exceptional air permeability and stretch to keep you in your sweet spot for longer.

　　Translation: its wicked breathable and easy to move in. For cool weather climbing, running, hiking, skimo, and other high-output activities, that kind of midlayer is ideal.

　　According to Patagonia, the Nano-Air Ultralight Hoodie and Pullover wick away moisture and keep you dry when youre working up a sweat, while the insulation thermoregulates so you dont lose too much heat.

　　Then, when you dont need to wear it, Nano-Air Ultralight packs away into its own pocket.

　　Less Than 10 Ounces, Premium Price

　　(Photo/Patagonia) The mens Patagonia Nano-Air Ultralight Hoody weighs 8.8 ounces, and the Pullover weighs 7.7 ounces. The womens versions weigh even less, at 7.6 ounces and 6.4 ounces, respectively.

　　For perspective, there is only one midlayer on GearJunkies Guide to the Best Midlayers that weighs less. The mens Summit Series FUTUREFLEECE Full-Zip Hoodie from TNF weighs just 7.3 ounces, a scant 0.4 ounces less than the Mens Nano-Air Ultralight Hoodie. So Patagonias new pieces compete with some of the lightest midlayers available — at least, weight-wise.

　　Price-wise, the new Nano-Air Ultralight line comes at a Patagonia premium. At $250 for the Hoodie and $200 for the Pullover, these are not cheap midlayers (but technical ultralight gear rarely is).

　　Other Features

　　(Photo/Patagonia) Beyond the featherweight insulation, Patagonia constructed the Nano-Air Ultralight jackets with a 100% recycled polyester ripstop shell and lining. The fabric is also abrasion-resistant, and the shell is treated with a PFAS-free DWR finish for shedding light moisture (emphasis added — this is not a rain jacket).

　　Each Nano-Air Hoodie and Pullover has stretchy, moisture-wicking, and quick-drying Capilene Cool Lightweight cuffs. The jacket and hoodie both have a slim fit, meant to accommodate a climbing harness or a backpack.

　　Patagonias Latest Lightest

　　(Photo/Patagonia) If the new Ultralight family is any indication, Patagonias popular Nano-Air line will continue to evolve and expand. How do these latest (and lightest) additions to the Nano-Air family perform against their predecessors?

　　We cant say for sure — yet. GearJunkie editors are getting their hands on the Nano-Air Ultralight and will be testing one in the next few weeks. Stay tuned for the review!

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