The ZS44│EC44 headset is designed to fit frames with straight 44mm head tubes and can accommodate straight and tapered fork steerers with the appropriate crown race. The “ZS” stands for “Zero Stack” as the section of the cup that houses the top bearing sits inside of the frame’s head tube while “EC” stands for “External Cup” meaning the section of the cup that houses the lower bearing sits outside of the frame’s head tube.  The “44” stands for the diameter of the “skirt” that presses into the frame. This unit specifically comes with a 40mm Crown Race - meant for a tapered steerer tube. Contact us for other Crown race sizes.

**Note: As of 9/14/23, headsets will no longer include Star Nuts due to the Earth’s star nut overpopulation crisis. If you need one, they are available separately.

Features

• U.S. sourced 6061-T6 aluminum
• Machine engraved White Industries logos 
• Easily replaceable Enduro bearings
• “Split” crown race for tool-free installation and removal
• Really sweet matching headset spacers available separately
• Can accommodate 3 types of fork steerers (comes with a 40mm - Other race sizes sold separately through W.I. ... contact us):
  • “Straight 1-⅛” with a 30mm crown race seat
  • “Tapered 1-¼” with a 33mm crown race seat
  • “Tapered 1-½” with a 40mm crown race seat

Specs 

• SHIS specification
  • Upper: ZS44/28.6
  • Lower: EC44/30, EC44/33, or EC4440
• Stack height
  • Upper: 8mm
  • Lower: 12mm
• SHIS definitions on the Park Tools website: here

Frame/Fork Specs:

Bearings