Tundra series freezer panels have a very unique freezing point of 5 degrees F and are designed to help maintain a consistent freezer temperature in coolers. While not as cold as dry ice, tundra freezer panels can be used as a suitable replacement. The panels have been shown to maintain days of frozen temperatures in controlled testing. Due to its low freezing point, tundra freezer panels can take 18-24 hours to freeze. Turn freezer to the lowest setting to ensure freezing. It is recommended that these panels be used to maintain frozen goods. Use weight equivalent to dry ice needed for great reusable results. Store in freezer when not using so they are ready when needed. The ice size is large.