What Our Gearhead(R) Experts Are Saying:"I grab the S/Lab Ultra 12L Set Hydration Vest for ultras or big training days when I need more capacity without sacrificing stability. It's incredibly lightweight for a 12-liter vest, and once it's on, it feels like part of my torso. The breathable fabric keeps things cool over long hours, and the expandable zipper is a clutch feature for adjusting storage as I shed layers. The included soft flasks ride secure and accessible, making this vest a true workhorse for distance missions."We count on the Salomon S/Lab Ultra 12L Set Hydration Vest when our longest days demand unwavering stability, efficient hydration, and lightweight comfort. Created alongside ultra-distance athletes, this vest is built to disappear into our stride-even when fully loaded for hours on rugged trails. Its breathable fabrics and body-wrapping fit help maintain comfort as temperatures rise and distances stretch deep into the day. With 12 liters of capacity and an expandable zipper, the S/Lab Ultra 12L adapts as our gear needs shift. Front pockets position hydration within quick reach, keeping the included soft flasks steady while we navigate steep climbs and flowing descents. Smart storage throughout the vest helps us manage nutrition, layers, and required race essentials without adding unnecessary bulk. Designed for long-haul performance, this vest supports the mental and physical grind of true endurance running.