A quality chuck will never cause you frustration, so trust the Silca 17-4 Stainless Steel Presta Chuck
The iconic Silca 17-4 Stainless Steel Presta Chuck (formerly the 30.0) has been updated - the classic brass material has been replaced by the much more exotic 17-4 Stainless Steel, a precipitation hardening stainless utilized in aerospace, petrochemical processing, military aircraft, and even as ultra-high strength bicycle tubing.
Whereas brass may have been a material to last a lifetime, 17-4 is a material to last many lifetimes. 17-4 is more than six times stronger than brass, resulting in parts that last longer and are nearly impossible to damage or wear out.
The utmost care has been taken to machine the part using mono-crystaline diamond tooling to get the perfect surface finish, while the final feel of the part benefits from an investigation into more than 20 different styles and depths of knurl so that it will feel 'just-so' in your hands as it provides a lifetime of useful enjoyment.
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 five times 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.
Iconic Silca Presta Head Design - in use by more pro team and shop mechanics than any other!
17-4 Stainless Material, 6X the strength and 2X the hardness of Brass
Full Synthetic Elastomer 242 Gasket
Five times the durability of traditional rubber materials
New Two-Stage gasket sealing geometry optimized for all Presta valve stems
Pressure amplifying dome geometry uses air pressure to clamp valve stem
Schrader valve thread on hose side threads into any Schrader compatible hose attachment
Hand-Crafted with pride in Indianapolis, USA