Description: 【Sealed Bearing】: Equipped with sealed deep groove ball bearings, this headset ensures high speed performance, The metal seals effectively retain lubricants within the bearings, providing good dust and water resistance 【Smooth Fork Integration】: Designed for seamless integration with your bike's front fork, this headset allows for smooth and effortless steering, enhancing your overall riding experience 【Compatibility Specifications】: Suitable for frames with a head tube inner diameter of 30mm (both top and bottom) and forks with an upper outer diameter of 25.4mm and a lower outer diameter of 27mm 【Construction】: Made from aluminum alloy materials, this headset offers durability while maintaining a lightweight profile, ensuring long time performance on various terrains 【Compact】: The bicycle bearing headset comes in a compact size of4.9cmx4.9cmx6cm/1.93inchx1.93inchx2.36inch, making it easy to handle during installation or replacement processes Specification: Material: Aluminum Alloy     Size Chart: 4.9cmx4.9cmx6cm/1.93inchx1.93inchx2.36inch Package Includes: 1 Bike Headset Note: Please allow slightly errors 1-2cm/0.39-0.79inch differences due to manual measurement.