Point Gaskets - Packing unit seal gaskets for plunger-fillers (replace original innards of Sheaffer or Eversharp packing units) made of fluorocarbon rubber for maximum durability and chemical resistance. Fluorocarbon seals are extremely durable, resisting wear & weathering far better than standard synthetic rubber seals. Estimated life span in industrial settings is up to 20 years, versus 2 to 5 years for butadiene.