The Salomon Adv Skin 8L Set Hydration Vest is uniquely shaped to provide you with a comfortable and secure fit for your runs. This unique shape eliminates pressure on your chest when it is fully cinched down. When it's cinched, it eliminates bounce while still allowing you to comfortably breathe so you'll barely know that it is there. The integrated soft flasks have a unique shape as well to match the contours of the vest so even when full, you won't experience uncomfortable pressure. Aside from a comfortable fit, the hydration vest features multiple pockets that accommodate the snacks, chews, and other small essentials you'll need during your run. Additionally, multiple pole holder options allow you to conveniently attach and secure your poles when you don't need them. And finally, when you're out on longer runs or require additional hydration other than what the two soft flasks provide, an internal sleeve accommodates a hydration bladder to ensure you stay refreshed through the miles.