Review on Lightweight Mubasel Gear Hydration Backpack with 2L BPA Free Bladder - Keep Liquids Cool for 4 Hours - Ideal Outdoor Sports Gear for Running, Hiking, Cycling, and Skiing by Dustin Miller

I've used this hydration pack a few times while running. It works well. As other reviewers have mentioned, after filling it with water I turn it upside down and suck out the air to keep it from spilling. It sits well on me (38 in the chest) and moves very little when almost empty. It's not enough to be annoying, but the movement could probably be eliminated if the manufacturer added an elastic waist strap with a buckle. I run in the south (90 degrees, 55% humidity) so the pack and straps get soaked where they touch my back and shoulders. The fabric absorbs very little sweat and dries fairly quickly when hung on a hook.