expanded PTFE sheet is manufactured by expanding 100% virgin PTFE that uses a proprietary process to produce uniform and highly fibrillated microstructure with equal tensile strength in all directions. The resulting product exhibits characteristics significantly different than conventional PTFE sheet. Expanded PTFE is much softer and more flexible than regular PTFE sheet, so it conforms easily to irregular and rough surfaces. In addition, the material is easier to compress and minimizes creep and cold flow.