Packi Backpack Cooler Throw the Packi Backpack Cooler over your shoulder to bring the party wherever you go. Bonus: you can add two of your favorite Swigs to the side pockets! Extra-Thick Foam Insulation Closed-cell technology provides premium temperature retention. PVC-Coated Durable Exterior Polyester shell is weather and waterproof. AquaSeal Lining Heat-welded seams create a leakproof, food-safe interior.