GFO fiber packing is made from 100% expanded PTFE fiber.GFO fiber packing is a pliable packing that is easy to install and lasts indefinitely. GFO fiber packing is a continuous-length packing, that when compressed, forms into a cohesive cylinder, thus eliminating the need to cut and form packing rings. GFO fiber packing is chemically inert, with few exceptions, over the entire pH range. Due to GFO fiber packing's excellent thermal conductivity and lubricity, GFO fiber packing is able to withstand shaft speed to 4,300 feet per minute.GFO fiber packing's self lubricating characteristic practically eliminates stem wear.GFO fiber packing withstands temperatures from -400°F to +550°F.The use of GFO fiber packing extreme versatility simplifies purchasing, reduces inventory.Thus the use of GFO fiber packing cuts costs even further.