Techni Ice! The most effective Ice replacement product on the market! Techni Ice stay colder for longer periods of time. The new release of 4 ply Techni-Ice Dry ice packs stays frozen much longer than previous versions! Techni Ice reusable ice 4ply consists of 2 non-woven textile layers, which encapsulate a specially formulated cross-linked polyacrylate polyalcohol co-polymer refrigerant combined with a post treated trade secret formula. A remarkable leap forward in ice pack technology utilising a cross-linked polyacrylate polymer that can be frozen right down to minus 190C (that's more than twice as cold as dry ice). Techni Ice reusable dry ice packs / gel packs can be used hot, cold or frozen can not only keep your food and drinks icy cold for days on end in the cooler but is also very effective at reducing battery consumption when placed in 12 volt fridge/freezers due to its eutectic qualities, which minimise thermostat activity.