This water resistant cover protects your pack and it's contents from the elements. Attaches securely with a hook and loop closure and drawstring. Includes three easy-to-use attachment points, plus a cinch system for secure fit. Bright yellow gives daytime visibility; reflectivity for low-light. Medium / Large fits packs between 1500 and 2300 cu in or 25L to 38L. CamelBak Got Your Bak Guarantee: If we built it, we'll Bak it with our lifetime guarantee. Materials: Coated nylon.