Neoprene collapsible koozies are more durable and stretchy which allows them to fit on more items. These koozies are made from neoprene rubber (wetsuit material) and are a step up from the traditional scuba foam koozie. The inner part of the neoprene can cooler is a felt like fabric to make it easy to slide it on the can or bottle. The middle portion is an neoprene rubber, and the outer fabric is polyester. The custom design can and neoprene bottle coolers are available in both a collapsible style and a not so collapsible when the bottom is sewn or glued in. The most popular sizes of neoprene koozies are 12 oz but they are available in sizes to fit wine bottles and growler bottles up to 64 ounces in size.