Designed and endorsed by Scott Jurek, the SJ Ultra Vest gives you the best weight to volume ratio of any pack of any kind while giving you an optimal feature set combinded with comtemporary styling. Weighing 7 ounces without the included water bottles and 11 ounces with the two included Ultimate Direction 20 ounce bottles, the SJ Ultra Vest keeps your load light while still keeping you hydrated. The SJ Ultra Vest also gives you plenty of room for you gear with 9.2 liters of space that includes a 6 liter main compartment, 1.7 liter back pouch, and 1.5 liters of zippered pockets. The SJ Ultra Vest also accepts a 70 ounce reservoir (not included) if your next run, event, or outing requires more water than the water bottles will provide.