[Mike Martus]

If the material is on the additional material list it is a legal material.

If the material is "sheet Rubber" then it is legal sheet rubber. If the material is named/sold as a "Widget" then it is not sheet rubber and is illegal as a Widget is not on the additional materials list. Its configuration of raw materials does not make it something it is not.

Question: May we make wheels?
Answer: Yes as long as the materials are on the additional materials list.

Question: Can we use conveyer belt?
Answer: Show me conveyer belt on the additional materials list. I only see V-Belts.

Question: What is the definition of a wheel?
Answer: Give Webster a try.

Question: Is no slip rug backing sheet rubber?
Answer: The product name answers the question. It is no slip rug backing.