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  • Bontrager Headset Expander Plug and Top Cap
Bontrager Headset Expander Plug and Top Cap
Bontrager Headset Expander Plug and Top Cap

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Bontrager Headset Expander Plug and Top Cap

Model W547432
$26.99 Comp. Value Sale price

Peace of mind for your carbon fiber steer tube.

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Genuine replacement parts

A safe and secure alternative to the traditional star nut for carbon fiber steer tubes.

This expander plug can be easily installed in all Trek 1-1/8" carbon fiber steer tubes.

Product details

  1. Approved for use on all Trek carbon fiber 1-1/8" steer tubes
  2. Always install one spacer above the stem on carbon fiber steer tubes
  3. Do not use on aluminum steer tubes in place of a traditional star nut
  4. Torque inner expander bolt to 9-10Nm
  5. Torque top cap bolt to 4Nm