1. The pack have thick insulated layer ,the insulated bladder compartment keeps your liquid cool or hot for up to 4 hours. 2. This Hydration packs are designed specifically for road cycling /running/ Hiking , that’s Compact and low-profile keep your body functioning at peak performance whether you’re training for a marathon or cycling. 3. The 3L liner inside detaches from the backpack for easy cleaning and assembly to stop a leak free outdoor experience. 4. Internally the hydration pack contains a separate pocket for other items, such as a phone, first aid kit, and snacks. 5. The hydration pack is your perfect choice for cycling, camping, running, rave , kayaking. 6. A decent Holiday Gift for families and friends who love outdoor sports.