This standard jewelry rubber is manufactured in the city of Akron the polymer capital of the world, with only purified natural gum rubber. A strict process control ensures a high quality rubber consistently from batch to batch. You will not find organic contaminants as in other brands. The overall performance of this rubber has excellent overall qualities such as cutting, tear strength, elongation, fill, and reproduction. This flex grade rubber strip (durometer 35 shore) has dark blue backing and is soft and pliable. Suited for detailed patterns. It has only 2.3% shrinkage. Measures 18" Wide.