This teaching skeleton is wired for natural movement and features a removable skull with the calvaria cut. Miniature springs hold the mandible in place to demonstrate TMJ problems. Tiny screws hold arms and legs in position so you can bend the extremities in all directions. All the bones are molded individually, except in the hands and feet. Although the basic appearance and functional value of this skeleton is excellent, there may be flaws in the construction (such as rough plastic, protruding wire, chipped paint, etc.). All hardware on the skeleton is stainless steel.