Rocket 3 Hydration Vest
"Perfect—it stays in place. The side panels are made of 500 fabric, and they squeeze the chest a bit for women, but once you’ve had a little to drink, they become more flexible and conform better to your shape. Perfect for a 2-hour run, for example; for anything longer, you’ll need to go up a size. One small criticism: the front pockets are a bit deep. If you slip something inside—like keys or other small items—you won’t lose them, but on the other hand, reaching in to grab something like a energy bar is much more difficult."
