GraviTrax Expansion Tunnels fidget How much power does your

How much power does your ball need to loop the loop

A complete writing set so you can send letters to your friends at Hogwarts

simply wipe down the inside of the bag with a damp cloth

freefalls and even a cannon

Do it again and again and again

GraviTrax Expansion Tunnels fidget How much power does yourraviTrax Expansion Set: Tunnels Create the element of surprise with the GraviTrax Tunnels Expansion set! Use the tunnels to hide the marbles as they travel through your track. Combine the tunnels with your GraviTrax Starter Set for added mystery to your track. Will you be able to keep your eye on the marble as it rolls through the tunnels? GraviTrax Tunnel extension is a great tunnel system and provides on the ball track for many moments of surprise.