: Essential for leaking air or oil. They often include U-cup seals (typically 0.5in/12.7mm inner diameter) and various metric O-rings (like 21x2mm for the bottom cup).
Regular bike tools won't always cut it for a Headshok. You might need: cannondale-headshok-parts
If you are planning a rebuild, these are the typical components you'll need: : Essential for leaking air or oil