[Multi-compartment and compact design] There are 3 multi-functional compartments, you can place your items in an orderly manner. The front opening pocket is matched with the Molle system to maximize the loading function. This hydrate backpack is compact and low-key. It feels light and stable on the back without resistance, allowing your body to perform at its best. [Professional 3L water bladder] It is made of odorless EVA material without bisphenol A. There is a 3L water bag inside that can be removed from the backpack for easy cleaning and assembly. This rubber mouthpiece has a simple on-off valve that can stop the flow of water when needed, ensuring that there is no leakage in the outdoor experience. [Practical function] The adjustable shoulder strap helps to fix the kettle according to your needs. The soft breathable mesh back speeds up the air flow and keeps your back cool. The foam padded shoulder straps are very comfortable. The safety whistle is built into the chest strap. This is a perfect hydrating backpack, suitable for hiking, running, mountaineering, and cycling colour: black + army green Material: nylon + EVA Size: 47x26x14CM Package Contents: 1 x water bag backpack 1 x water bag