Seattle Sports AquaSto Big Mouth Water Carrier is the better water storage/carrier solution. Lightweight PVC & BPA free material create a strong, but super-collapsible water carrier. Perfect for camping, boating, hunting, backpacking, and more. Big Mouth design allows you to easily fill, pour, and use alternative water purification systems. Threading works with most Nalgene® & CamelBak® lids. Compatible with MSR® Miniworks EX water filter.