SLS3 Running Hydration Vest | Small Trail Runner Vests | with 2 Bottles - 19oz - 34oz | Running Water Backpack Men Women | Ultra Jogging Back Pack ATTENTION: THE VEST IS NOT INTENDED FOR SMALLER / THINNER ATHLETES - Works best at 135 lbs - 185 lbs - max chest 40". Fully adjustable strap system allows you to secure the vest to fit your body shape. THE VEST WILL NOT BE A GOOD FIT IF YOU HAVE A THINNER BODY TYPE (THE STRAPS WON`T TIGHTEN ENOUGH). Lightweight design keeps you cool - you might even forget youre wearing it! We do recommend wearing a short sleeve shirt while using the hydration vest. SMALL backpack pocket (6.5" x 10.5") gives you space for an extra water bottle, bladder or gels. THIS IS NOT A VERY BIG VEST - IT ONLY CARRIES ESSENTIALS! The Lightweight Hydration Vest / Backpack is perfect for trail running, marathon running, hiking and cycling with easy access front pockets to keep your keys, iPhone and ID within reach. Easy access to the 2 front bottles means on-the-go, seamless hydration - a total of 19oz. Why bother with a bladder that is bulky and a tube that is hard to keep clean?