The new 242 gasket utilizes a high tech and very red, fully synthetic elastomer base material rather than a carbon black filled natural rubber of previous gaskets. This unique bright red gasket borrows from industries which require air-tight seals in the harshest of environments, and tests to a life expectancy of more than 5X the carbon filled rubber or Buna-N materials used previously. New Two-Stage seal geometry seals on both valve stem and at the base of valve core threads resulting in a more positive seal and improved durability. The new gasket slips onto the valve stem with a positive and satisfying ‘click’, while unique internal geometry actually utilizes line air pressure to compress the gasket onto the valve stem: the higher you pump, the harder it grips the stem!