BPA FREE FOOD GRADE MATERIAL: Made from tasteless and food grade polyethylene film, Eco-Friendly, Reusable and Refillable, 4 environmental friendly 5L water containers, well meet your demands of water storage in different occasions. WIDE APPLICATION:Suitable for outdoor BBQ, camping, and domestic water. Great for survival & emergency kits. Store water, milk, tea, juice, alcoholic drinks also dry goods like beans, grains, coffee etc. It can be used as a petrol bag when in an emergency case. HUMAN COLLOCATION: Hakkin provides you with two more water bag caps. It solves the trouble that the water bag can not be used due to the loss of the bottle cap. And the caps are universal. INNOVATIVE DESIGN & LEAK-PROOF CAP: Unlike ordinary water bag, the large screw-on cap provides a leak-proof seal, the large 1.65" inch bottble opening for easy filling and pouring, wear-resistant handle hook for hanging on a backpack, convenient to carry, will not hurt your hand. SPACE SAVING AND PORTABILITY: Foldable and lightweight, you can roll it up for storage and carrying, small footprint, perfect outdoor drinking tool. With sturdy material, freezable, and can be used as a mobile water tank or a car water tank, which is more convenient than a traditional plastic water tank. It should be noted that the suitable temperature of the water bag is -10C~70C.