The PRO Gap Cap Expander Carbon is PRO's lightest headset top cap and expander, built to trim grams from your cockpit without compromising on a clean, secure front end. Designed specifically for carbon steerer tubes, it pairs an alloy expander body with a carbon top cap for a premium, weight-conscious finish.

Highlights

  • PRO's lightest Gap Cap Expander at just 24g - 16g lighter than the previous version
  • Alloy expander body with a carbon top cap
  • Purpose-built for carbon steerer tubes, where a traditional star nut isn't suitable
  • Compatible with all stems for an easy upgrade to any lightweight build
  • Discreet black finish

Compatibility & fit

Fits 1-1/8" (28.6mm) carbon steerer tubes. This is the 25mm length version (PRHS0118). For 1-1/4" steerers, choose the matching PRHS0119 variant. As an expander-style top cap, it is the correct headset preload solution for carbon forks and works with any stem.

Covered by PRO's manufacturer warranty against defects in materials and workmanship. For any warranty claim or support, return the item to Tune Cycles and we will manage the process on your behalf.
  • PRO's lightest Gap Cap Expander - just 24g (16g lighter than the previous model)
  • Alloy expander body with a carbon top cap
  • Designed for carbon steerer tubes
  • Sets headset preload via an internal expander (no star nut required)
  • Compatible with all stems
  • Black finish, 25mm length
TypeHeadset top cap with expander plug
Steerer size1-1/8" (28.6mm)
Steerer materialCarbon
Length25mm
ConstructionAlloy body with carbon top cap
Weight24g
ColourBlack
Stem compatibilityAll stems
Article numberPRHS0118
SKU SHM-PRHS0118
Barcode # 8717009592833
Brand PRO