Description: Capacity and Comfort: This Hydration Pack is a lightweight, breathable backpack with a capacity of approximately 5L, comfortable to wear during outdoor activities like cycling, running, or hiking. The material used is water resistant polyester that is light, thin, comfortable, and resistant to wear and tear.Reflective Design for Safety: The hydration backpack has a reflective design that enhances visibility in low light conditions making it for night time activities. Size43cmx28cmx8cm/16.93inchx11.02inchx3.15inch.Organized Storage: This hiking backpack can accommodate your essentials while keeping them organized. It features a waterproof aluminum foil compartment for separating wet and dry items to prevent soiling of clothes.Convenient Design: The backpack features convenient side storage pockets and a top handle strap design for easy carrying by hand when needed, great for long outdoor adventures.Adjustable and Versatile: It features quickly disassembled and adjusted making it easy to use. Hydration Backpack is designed to fit snugly against your back for maximum comfort and flexibility. Specification: Material: Polyester Size Chart: 43cmx28cmx8cm/16.93inchx11.02inchx3.15inch Package Includes: 1Hydration Pack1 Water Bladder Note: Please allow slightly errors 1-2cm differences due to manual measurement.