This marble is HOLLOW and HUGE!! In fact, it's the largest hollow marble I've ever seen. I don't know how Wil pulled this one off, but it is amazing in hand. It is a new world that you will LOVE exploring, as the tiny details in the glass are just fascinating. I love how he did the clouds on this one, the best 3D cloud tech I've ever seen. One of a kind to the max, as I've never seen even another hollow marble from Wil, much less one of this magnitude! Signed 'WM 04'.