"What Our Gearhead® Experts Are Saying:""This is my go-to midlayer for high-output climbs and skintrack missions. It moves with me, dumps heat when I’m charging uphill, and still insulates well when I stop. The Ventrix™ panels in the underarms are a game-changer.""We built the Summit Casaval Hybrid Jacket for missions where movement and temperature regulation go hand in hand. The North Face integrates Ventrix™ stretch insulation and body-mapped fabrics to create a midlayer that moves with us and breathes when we're pushing the pace. Whether we’re bootpacking toward a ridgeline or charging through alpine scrambles, this jacket delivers just-right warmth without weighing us down or overheating. Thoughtful construction sets this jacket apart. Underarm panels with perforated Ventrix™ open up with movement for adaptive airflow, while the durable outer is treated with a non-PFC DWR finish to shed light snow or drizzle. Stretch-woven cuffs, a fitted hood, and a single-point hem cinch dial in the fit. Dual zippered hand pockets, a chest pocket, and a secure left pouch stash all our essentials on the move."