Altra Apparel Size Chart Be invincible with every step. Meet the next big thing in running gear. The first of its kind, the Altra StashJack gives you the flexibility to take your jacket on or off without derailing your momentum. With a convenient hip belt pocket, you no longer have to stop your run to store your jacket when it’s not in useyou can now pack it away with ease. And the StashJack features revolutionary open-back accessibility for easy access to your backpack at any time. At just 3.3 ounces, the StashJack will streamline your running experience. Features: – Wind and Water Resistant – Logo Reflectivity – Take On and Off Without Stopping – Packs Into Hip Belt Pocket – Open Back for Easy Backpack Access – Trimmed and Flat Lock Seams – Loose Fit – Back Length: 26.5″ (based on size Medium) – 100% Nylon ripstop – Fabric Weight: 3.3 oz.