Watch young scientists and engineers uncover the ocean's secrets with the LEGO Technic: Deep-Sea Research Submarine. Using 413 pieces, kids can build and explore realistic features like rotating propellers, a grabbing arm, and a transparent cockpit. Using the LEGO Builder app, kids can get an intuitive building experience with 3D rotation and progress tracking. | LEGO Technic: Deep-Sea Research Submarine - 413 Pieces (42201)