UTOBEST Running Vest Running Backpacks Lightweight Functional Hydration Pack 5L, with 1.5L Hydration BladderHYDRATION SYSTEM: UTOBEST running vest compatible with 1. 5 L water bladder (1. 5 L bladder is included). 3 front storage pockets with zippered for phone, keys and other items. 2 elastic front pockets for easy access to hydration, for hydration needs during running MAXIMUM COMFORT: The hydration running vest is adopt to premium nylon and polyester fabric, which is stretchy, sweaty and breathable. Extremely light backpack, only 250 g, you dont even