FlexiKold Gel Cold Packs are more flexible and stay colder longer. Why? It's the Gel. Unlike the bentonite ingredient used in competing cold packs, FlexiKold is powered by a proprietary gel interior that remains smooth and pliable when frozen. And since the gel stays colder longer, less gel is needed, allowing for a thinner, more user-friendly construction. FlexiKold Gel Cold Packs provide superior contact with the treated area and easily conform to any part of your body. Available in multiple sizes!