The Ultra 4 from CamelBak was built for people gearing up to run a marathon or longer. It carries water, a light rain shell, energy food, a phone, gloves, hat, keys, and not much else — perfect for long days on the trail where you don’t want a normal pack weighing you down.
I reviewed it while training for the Red Rock 50 Ultra-Marathon, including a multi-week trial on runs around southern California. Here’s a first look from my test.

The Gear: CamelBak Ultra 4 hydration vest ($115)
Test: During about 200 miles of trail running I put the pack to the test on outings varying from one to several hours in length. I also ran a marathon in it last month. Once you dial fit with the vest straps it feels great for hours on a run.
Details: The vest-pack comes with a GearJunkie-approved Antidote reservoir. Two pockets in front can hold water bottles (not included). That adds up to more than a gallon of water on this vest at its max. Extra equipment is carried in zippered compartments on back. Trekking pole straps on back. A sweat-proof storage compartment is made for keys and a phone.

