Only when you buy in bulk will your $100 sample deposit be returned.
The backpack's back is constructed of breathable cotton, which efficiently relieves strain on the back
The water bladder is constructed of EVA food-grade plastic, and the water exit is created with a seal to guard against contamination
The water bag connected layer may store mobile phones, wallets, and other goods, and the Velcro closure makes it more practical. Glasses can be placed in the circular buckle on the back strap of the bag.