Thanks to the versatile elements, even longer GraviTrax tracks can be built and new ball tracks can be discovered for even more ball action.Combined with any GraviTrax starter set, the Extension Building brings even more variety and ball fun to the GraviTrax universe; how much longer can the ball roll with the new elements? GraviTrax is the flexibly expandable and interactive marble run system for children aged 8 and over; with GraviTrax, entire marble run worlds can be created; all GraviTrax products in the three lines GraviTrax, GraviTrax PRO and GraviTrax POWER can be combined with each other; an ideal gift not only for birthday for boys and girls. GraviTrax Core unleashes the inventive spirit and offers endless possibilities beyond imagination; the versatile elements allow a playful introduction to the GraviTrax universe and offer plenty of space for creativity and free building; everyone can get started right away and create extraordinary tracks Add some vertical challenge and take your marvelous marble run to new heights with the “GraviTrax Building Expansion” set! With over 25 additional components and endless possibilities to design a different track every time you play, experiment with combinations of height tiles, base plates, freefalls, switches and extra level. A cool addition to any “GraviTrax Starter-Set” — boost your building skills and race your marbles to the finish! Experience the power of gravity and educational fun today! Comes with 2 base plates, 1 transparent level, 8 large height tiles, 4 small height tiles, 2 switches, 1 3-in-1 tile, 1 vortex, 1 finish line, 4 basic tiles and inserts (2 catchers, 1 freefall, 1 splash, 1 landing).