Abstract: An insulation sleeve, also known on a koozy, is adapted to fit on a one-gallon jug to keep its contents insulated. The insulation sleeve can wrap about the one-gallon jug, keeping warm liquids inside the jug warmer longer than without the insulation sleeve, and keeping cold liquids inside the jug colder longer that without the insulation sleeve. The insulation sleeve could be made of a insulation material, such as neoprene. The insulation sleeve could be made out of a single material, or multiple materials. For example, the insulation sleeve could include a rubber base to help minimize wear through the base of the insulation sleeve.