Expanded PTFE fibers incorporating graphite are used in the manufacture of this unique packing style. Offers high self-lubricating capacity, high chemical resistance and a fairly good shaft speed tolerance. Will never harden, it is self molding and ideally suited for sealing worn shafts and pumps in poor conditions. Recommended for centrifugal, plunger and piston pumps, valves and many static applications, offers one of the most popular sealing material solutions due to its great price/quality ratio.