The DOMETIC COOL ICE passive coolers offer a key benefit–they require no power supply. Instead, they are rotomoulded to be lightweight and easy to handle with a highly effective polyurethane foam insulation, combined with a tight closing labyrinth seal. Once the cool packs or ice cubes have been placed inside, they will keep groceries, fish, bait and wild game fresh, even for several days at a time depending on use and weather conditions.