- Magnetic self-sealing hydration bladder for backpacks with unique closure technology.Climbing, biking or hiking - a good water supply is essential. However, you don’t want to spend a lot of time preparing? The HERMETIC hydration bladder is filled with ease and closes immediately and securely. Thanks to the patented closure technology, easy handling is guaranteed, allowing you to start your sporting activity quickly and effortlessly. The hydration bladder has three wide-opening rows of magnets that seal automatically and hermetically – absolutely leakproof. The additional SNAP closure on the pocket flap can be operated with one hand and prevents unintentional opening of the hydration bladder in the backpack during activities.Additionally, the wide opening allows users to quickly and simply clean and empty the bag.