Description: Educational Toy: This DIY undersea science experiment is an educational tool that demonstrates the principles of buoyancy and gravity.Working Principle: Kids submarine toy underwater by controlling buoyancy and gravity. When the balloon inside a submarine is empty, gravity exceeds buoyancy, causing the submarine to sink. As the balloon gradually fills with air, buoyancy increases while gravity remains almost constant, causing the submarine to slowly when buoyancy exceeds gravity.Material: This submarine bath toy set is made of durable material, The size of the submarine body is 18.5cmx7.5cmx5.5cm/7.28inchx2.95inchx2.17inch, and it is equipped with a hose about 45cm/17.72inch long.Nice Gift: Each mini warship set package contains a DIY submarine science experiment , a great gift for kids who love experiences.Fun Toy: This toy submarine kits not only provides fun but also inspires children aged 3-9 to curious about science. Size Chart: Submarine Size:18.5cmx7.5cmx5.5cm/7.28inchx2.95inchx2.17inchHose Length:45cm/17.72inch Package Includes: 1Kids Submarine Toy Note: 1.This is not infant toy, please take away from children to avoid eating.2.Please allow slightly errors due to manual measurement and different monitors.