The HAJKER is the optimal hiking day pack with a big 30L main compartment with a rolltop and an inner dry sack, waterproofing your gear for all kinds of weather. Store the stuff you need quick access to in the two zippered side pockets and compress it all together from the outside to get slimmer profile and a stable backpack that doesnt bounce when you are out exploring, climbing, or running in the roughest terrain. Do you hate it when your water freezes? We sure do! The included Thermo Cell insulation technology uses your body heat to protect the drinking tube and the pockets on the shoulder straps, perfect for storing gels and food. The compression sleeve keeps the hydro pack in a tight and secure position (Hydration bladder is not included). The waist belt secures the lower part of the backpack and can also be detached and used on its own, like a hip-pack. You also got a helmet carry system that detachable and stored in a pocket when not in use. The pack also comes with an insulated water bladder pouch if you ever want to add a hydration bladder with the pack (bladder not included).