Silca Elastomer Seal for Presta Chuck 242

The Iconic SILCA 24.1 gasket has been updated and improved after more than 30 years in the market.  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 Silca Elastomer Seal for Presta Chuck 242 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 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!