• Encourage children aged 9 and up to explore the secrets of the oceans with this Deep Sea Research Submarine Toy Set (42201). This model has features found in real submarines such as a cockpit with 3 rotating propellers, 3 air tanks, seats and controls. There is also an arm that extends to allow children to have their own undersea adventures by holding and lifting the keg accessory. This submarine model set is one of the LEGO Technic sets with realistic movements that can introduce young model lovers to the engineering universe. This set is a great gift for boys and girls who love buildable toy tools. Using the LEGO Builder app, you can guide children by zooming in on the models in 3D, rotating them, saving the sets, and tracking their progress.