This was a part created for a training class I first wrote in maybe 2003. One of the curiosities of this part is that there is a single edge that goes all the way around the part, and there are no flat surfaces on it anywhere. The part can be made using just a few features, but it takes a lot of practice to get splines correct. It takes a certain eye to get a nice shape on a part like this. The part was originally brought to me as a challenge by a student, and it was such a nice example, I have used it for other purposes as well.