Let's face it, nobody wants to carry water. However with the Osprey 2.5L it makes those day hikes a breeze. Easily attaches in your water pouch of your hiking bag. Easy to open and re-fill, and have never had this bag leak a single drop of water. My bag has been turned upside down and rolled over down a hill and the Osprey water reservoir did not fail. The quick connect hose and mouth piece is very comfortable and also has an easy locking feature to prevent accidentally discharging water when not in use. The magnetic connector will allow you to position the mouth piece just about anywhere that fits your needs. The staff were super helpful when I was trying to decide what water reservoir was right for me. HIGHLY RECOMMENDED!