The gasket uses unsintered PTFE tapes as the filler material. The PTFE filler provides superior chemical resistance and sealabining with strongly corrosion resistant metals, it can be applied for corrosive fluids, pure oxygen gas and vacuum lines. Feature 1. Sealability is superior to that of other SWG gasket. Usage is possible even with vacuum lines. 2. Excellent corrosion resistance makes it suitable for almost all types of fuild by selecting appropriate hoop materials. 3. Not used for glass or rubber lined flange, glass or porcelain flange.