Hikes, approaches, backcountry tours, a day at the crags – the exceptionally versatile Proton Crew gives you lightweight warmth, temperature regulating airflow, and freedom to move. Soft and comfortable, ultralight Octa® Loft insulation’s combination of warmth and breathability maintains thermal comfort. The air-permeable Fortius™ Air 50 outer is light, durable, and has performance stretch. A DWR treatment repels moisture. Midlayer or standalone – you’ll wear this for everything the mountain offers.