An absolutely top-of-the-line 1 1/8" - 1 1/2" threadless alloy headset for the most discerning rider. It features oversized sealed cartridge bearings, so packing and re-greasing bearings are a thing of the past.
Stack height is 31mm with a 40mm split crown race for easy installation.
Upper - EC34/28.6
Lower - EC44/40