ROKR Marble Night City 3D Wooden Marble Run PuzzleBased on great human engineering, this marble run is a stunning fusion of science and mechanical artistry. It features a self assembly 3D wooden puzzle with tower distributors and a dynamic track system that sends steel marbles racing through slopes and twisting turns. Build the set, crank the handle, and watch as marbles zip around in a mesmerizing display of motion and design ingenuity. This model breaks through material limitations by incorporating