The Summit L5 LT sports TNF’s new fabric Futurelight, billed as a big step forward in lightweight, water- and windproof breathability. Weighing 22–23 ounces, it’s very light for an alpine shell—and proved the effectiveness of Futurelight when a downpour rolled in at 9,000 feet at Jurassic Park, Colorado. I got wet in my T-shirt before I was able to get the jacket on. It kept raining—we bailed—but my shirt was dry by the time I reached the car despite the downpour. Impressive! And I didn’t feel clammy even with the fabric next to my skin. The L5 LT is stripped down, with a bellowed, extra-large chest pocket for skins or gloves; a mesh internal pocket and stuff sack; and an adjustable, stiff-brimmed, helmet-compatible hood.