Campagnolo Record threadless headset lightweight and for 1 1/8" steerer tubes. The name Record should tell you all you need to know - smooth bearings that will last years. It has a 26.4mm crown race of course. 
The Cycle Clinic stocks spare crown races and bearing kits for this headset.

  • Campagnolo Record threadless oversize 1 1/8" headset.
  • High grade ball bearings (caged and serviceable)
  • Self - centering bearing system.
  • Carbon fibre top cap and alloy fixing bolt.
  • Stack height 25.4 mm.
  • Weight - 110g