AUSQI 16qt Insulated Leak Proof Backpack Cooler, Keeps Cool for up to 36 Hours,BlackHeat preservation for 24 hours, cold preservation for 36 hours. Waterproof, Leak-proof, Lightweight, COMFORT, 16qt CapacityFeatures of AUSQI 16qt Insulated Leak Proof Backpack Cooler, Keeps Cool for up to 36 Hours,Black ?36 Hours Retention?Heat preservation for 24 h..