Description This Cane Creek 40-Series complete headset is the perfect upgrade for your Aventon track bike. The 40-Series was designed with three things in mind - performance, durability, and value. Both the top and bottom headsets are fully sealed, with Black Oxide bearings to keep dirt and water out. These headsets have solid build-quality and might be the last ones you ever buy. Applications: complete headset assembly comes with a short cover and fits IS42-top/IS52-bottom frames with tapered forks, such as: Aventon Cordoba 2017 (Limited Edition and Standard models) In addition to Aventon products, it can also fit many other makes/models. S.H.I.S. Dimensions: IS42/28.6-top and IS52/40-bottom, Cane Creek part #BAA0080UD SPECIFICATIONS TECH DESCRIPTIONIS42/28.6/H9/K|IS52/40/H1 TOP TYPEIS - Integrated TOP HEAD TUBE INSIDE DIA.42.00mm STEM CLAMP DIA.28.6mm TOP STACK HEIGHT9mm TOP BEARING TYPEBlack Oxide, Sealed BOTTOM TYPEIS - Integrated BOTTOM HEAD TUBE INSIDE DIA.52.1mm CROWN RACE SEAT DIA.39.79mm CROWN RACE TYPESteel, Face-Sealed BOTTOM STACK HEIGHT1mm BOTTOM BEARING TYPEBlack Oxide, Sealed MATERIAL6061 WEIGHT84g TECH DESCRIPTIONIS42/28.6/H9/K|IS52/40/H1 TOP TYPEIS - Integrated TOP HEAD TUBE INSIDE DIA.42.00mm STEM CLAMP DIA.28.6mm TOP STACK HEIGHT9mm TOP BEARING TYPEBlack Oxide, Sealed BOTTOM TYPEIS - Integrated BOTTOM HEAD TUBE INSIDE DIA.52.1mm CROWN RACE SEAT DIA.39.79mm CROWN RACE TYPESteel, Face-Sealed BOTTOM STACK HEIGHT1mm BOTTOM BEARING TYPEBlack Oxide, Sealed MATERIAL6061 WEIGHT84g