Description: 【Sturdy and Comfortable Material】: Crafted from water resistant nylon with a breathable honeycomb mesh design, this hydration vest offers flexibility and comfort, making it ideal for trail running, road running, and 【Ample Hydration Capacity】: Equipped with a spacious rear compartment and bottle holder, this Hydration Backpack Pack can accommodate both hydration bladders and bottles to meet your hydration needs during outdoor activities 【Adjustable Fit with Safe Features】: The lightweight backpack vest features adjustable shoulder straps for a great fit to your body shape. It also includes reflective strips for enhanced safe during nighttime runs or cycling 【Sufficient Storage Space】: This running vest provides ample pockets to store essentials like your phone, keys, raincoat, water bottles, and bladder while engaging in outdoor activities 【Versatile Use with Compact Design】: Designed specifically for road cycling, running, and hiking, its compact structure ensures stability on the back without creating significant wind resistance Specification: Material: Nylon Size Chart: 23cmx40cm/9.06inchx15.75inch Package Includes: 1 Hydration Pack Note: Please allow slightly errors 1-2cm/0.39-0.79inch differences due to manual measurement.