The CamelBak Unbottle 2L Hydration Reservoir is an easy way to add water to your gear arsenal. The Crux reservoir is wrapped in an insulated sleeve to protect your water from the fluctuating temperatures around you. This system has multiple attachment points to make strapping it onto a backpack or other setup a breeze. The ergonomic grip makes one-handed filling a breeze, and you don't even need to remove the sleeve to access the reservoir.