Collectible erasers? Sure? I had a couple of these from who knows back when but I found some more at a local dollar store so I bought every kind that I could find. So now I have six in total. I'm not sure what the story is behind why these were at the dollar store, considering that the copyright date is 2010 on the packaging, but that's fine, old stuff is cool too! Anyways, these "castings" are all 100% made out of erasers. They can be taken apart and put back together as shown below. These are definitely meant for children or to be actually used as erasers but I'm going to try to preserve them as a collector. I have no idea how long these will last before falling or breaking apart but we'll see! So far they all look great and I think it was a neat fun little idea. I wish I could find more! And oh yeah, "they are designed to build like a puzzle, and are known to erase better than some pencils!"