The CRESBI Stage Crate Cooler Insert fits perfectly in either the regular or the Colossal CRESBI Stage Crate. Keeps foods cold or warm at least 1 hour and in most cases, 2 hours. Zipper insures that no air will leak out or in. Collapses down when not in use for easy storage and carrying. They are not leak-proof for ice. Wipe down to clean. Regular size CRESBI Cooler Insert should only be used in conjunction with the stage crates and not as a stand-alone cooler. Colossal Stage Crate Cooler Insert is made of a heavy duty canvas with 2 zippers and a front pocket. The Colossal Thermal Insert can also carry a regular size CRESBI crate open or 5 collapsed.