The Iconic SILCA 24.1 seal has been updated and improved after more than 30 years in the market. The new 242 seal utilizes a high tech and very red, fully synthetic elastomer base material rather than a carbon black filled natural rubber of previous seals. This unique bright red seal 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 seal slips onto the valve stem with a satisfying 'click', while unique internal geometry actually utilizes line air pressure to compress the seal onto the valve stem: the higher you pump, the harder it grips the stem!

This design is so iconic we've found more than 20 companies worldwide making pump heads and gaskets copied from this, but none of them can come close to the precision and technology in our new seal

• Fully Synthetic Elastomer Base Material
• 5X the durability of traditional rubber materials
• New Two-Stage sealing geometry optimized for all Presta valve stems
• Pressure amplifying dome geometry uses air pressure to clamp valve stem
• Made in the USA