Geigerrig makes the best hydration packs I've found and they are perfect for day hikes when keeping hands-free fluids in you is essential. Their packs use a pressurized "hydration engine" with dual compartments for air and water. Pumping the air chamber up pressurizes the water compartment allowing you to spray the water from the hose. I can't tell you how handy this has been. The packs carry 2 or 3 liter bladders. I typically fill half with ice and the rest with filtered water before a hike and have ice cold water the entire time. The Rig 1210 is my go-to bag for trips less than 15 miles. My wife uses the Rig 710 because it's lighter, smaller and she doesn't drink as much. A also have the Rig 1600 for longer trips and used it exclusively for two weeks in Israel and Jordan recently. I have found their customer service to be stellar. That alone will bring me back.