Equalseal FG-SS Foil Inserted Flexible Graphite. Flexible graphite is one of the sealing industry’s top performers and the style most widely used is the .002"" stainless steel foil insterted. The foil instert adds handling strength, yet is still easy to fabricate because it is so thin. It is made from 99% pure exfoliated graphite flake and calendered into a highly compressible, premium grade sheet for industrial use. Equalseal FG-SS foil Inserted flexible graphite is equal in performance to Graftech Grafoil® GHR, SGL Polycarbon BSSC, and Garlock Graph-Lock® 3125SS.