Conveniently hangs on side of aquarium Tough, break-resistant plastic design Great for moving fish, plants, food, and tools The Aquarium Co-Op Catch Cup is the universal tool that every fish keeper needs. It can be hung from the side of any aquarium with ease and is used for shipping, breeding, moving, observing, holding plant trimmings, and a million other uses. This incredibly durable holding container is made from super clear plastic and is meant to withstand long-term use with your aquariums and fish. The plastic is pliable and break-resistant, even if you drop on concrete. We love to use these daily at the Aquarium Co-Op retail store.