The 40-Series is the workhorse of Cane Creek's headset line-up. Representing the balance of performance, durability and value, the series incorporates all the features necessary for a robust, lightweight, long-lasting headset. Zero stack uppers press into head tube with very little stack height. Lowers are either zero stack or external cup. Features: Sealed black oxide bearings Carbon-friendy compression ring captured in top cover, keeping shims in place Steel crown race with integrated seals Interlok spacer compatible Compatible with tapered 1-1/8" to 1-1/2" steerer tubes, or straight 1-1/8" steerers with a conversion crown race (sold separately) Specs: Bearing TypeCartridge ColorBlack Defined ColorBlack Crown Race40 S.H.I.S LowerEC49 S.H.I.S UpperEC49 S.H.I.S. Stem Clamp Diameter28.6 Threadless