What Our Gearhead(R) Experts Are Saying:"I've used the Trailborne 2. 5L Shell on everything from alpine hikes to bikepacking trips. It's super light, fully waterproof, and packs into its own pocket, which is perfect when I'm trying to keep weight down. The underarm vents actually dump heat fast, and the bonded details give it a clean, durable feel."When the weather shifts mid-ascent or rain rolls in during a long approach, we pull out the Columbia Trailborne 2. 5L Shell to keep our momentum-and our layers-dry. Its fully seam-sealed Omni-TECH(TM) fabric shields us from wind and rain while remaining breathable enough to stay comfortable on the move. From trailhead to summit, this shell is built to keep pace. Designed with bonded details and minimalist weight in mind, this shell includes underarm vents for airflow, a drop-tail hem for added coverage, and a two-way PU zipper that adds durability and flexibility. The hood features peripheral adjustment for a secure fit, and when the skies clear, the entire jacket packs down into its own hand pocket. It's the layer we count on when light and fast needs to meet fully prepared.