Features1.Plastic material: each cycl1 tube is make of plastic, durable to use for a long time, with stRIPSes on THIS appearance of connectors which makes it much easier for you to rotate, common size suitable for most bottles2.Easy to use: THISse bottle connectors are suitable to connect a bottle with little water or an empty bottle, you can shake THIS bottle horizontally 4 or 5 times, and THISn you will see THIS water rotate in THIS bottle3.Educational tool: our plastic tornado connectors have educational meaning, ideal experiment tool for school, classes which can help increase children's intelligence and stimulate THISir interest to physics and study4.Gift choice: if you want to find a practical and educational gift to your children or friends, our cycl1 tubes are nice choice, appropriate for Christmas, Birthday, and oTHISr holidays DescRIPStion:This tornado bottle connector is ideal experiment tool for school, classes which can help increase children's intelligence and stimulate THISir interest to physics and study.SpecificationsMaterial :PlasticSize: 3.2cm in diameter, 5cm in height Package Included1*Tornado Bottle Connector