Azarxis Hydration Running Vest Backpack Pack 5L 5.5L for Women and Men Jogging Trail Race Marathon Cycling HikingNylon Imported No Hydration bottle: Equipped with 500ml soft water bottles, the high quality hydration bottles are made of tpu material and they are bpa free. The hydration bottles have complete pressure tolerant and leak proof function, ensuring sufficient water in various outdoor activities Adjustable: The adjustable waistband makes the backpack fit you perfectly and prevent the backpack from moving, and wide mesh shoulder strap helps to reduce the