Traveling to and walking, hiking and just plain sightseeing in Yellowstone National Park, having a day pack that carries everything you need is a must.
This pack allows me to carry water with the hydration pouch which is a must with the high temperatures we are experiencing. It also allows me to keep my hands free to use bear spray if necessary.
I can carry snacks and pack out what I packed in and not spoil the surroundings as many people do.
Carrying the other must haves such as camera, selfie stick and my wife's must haves.