Assuming your are referring to the skull and the motor in the two pictures. They are molds, or sculptures. Nothing special, I have seen people use the styrofoam heads that are used to hold wigs for women, the arms of an old store manikin, or parts from toys, plastic model car parts. That's the thing when it comes to modding a PC, your mind is really your only limit. You can be creative and just about use anything that catches your eye. I hope this helps you.