The Unbound Series insulated backpack is a lightweight, durable and leakproof soft cooler designed to let you carry food and drinks anywhere. The design started out with a comfortable, sweat-free and ergonomic harness strong enough to carry 15 or 22 liters of your favorite food and beverages. Waterproof zippers along the perimeter allow easy access to the food-grade and BPA-free interior, and dry storage external pockets keep your mobile phone dry and safe. The Thermal Mapping technology means thicker insulation in the base, and lighter weight construction on top, keeping contents cold for up to 48 hours.