This is a fabulous piece! When marbles go through this, it looks so different from when they are running other wooden tracks. It seems like &quotvisible" is important and attractive for younger children. To tell you the truth, we bought this as a substitute for other item that was out of stock. Then, after we received this, it became our &quotmust have" piece. Thank you for the out of stock item!

This is one of the best marble run pieces ever! I never would have bought it because I thought that it looked like a boring accessory - it doesn't DO anything to the marble (like stop it or make a noise or change its direction or anything). But then we received it as a gift, and it has become one of our favorite pieces of all. It is totally enthralling to see the marble come out of the shadows of the blocks for a minute and pass through the glass tube. And it's a particularly easy piece for the little kids to use because it doesn't require any placement precision - once the marble is in the hole, it can't bounce out or go the wrong way. We love, love, love this one!

My son is obsessed with tubes -- wrapping paper, paper towels, etc., so it was no surprise he'd love this addition to his marble run. It's really exciting to build a big circuit, let loose a bunch of marbles, and watch them pass through the Glass Tunnel. Even our cat likes to follow the fun.