The Unzen 15 litre hydration bag is lightweight, sleek, and crafted to fit your natural riding position. Shimano shapes each part of the bag to create a "scrared monkey" hugging fit that stays molded to your back. . After installing your hydration system, just throw in your tools and favorite energy bar then tailor fit to your liking. So if you"re ready to unleash your own hidden power, try UNZEN by Shimano.Light Loop to atttach any light with a clip.Includes a 3.0 liter FDA approved BPA free Hydrapak resevoir.