Check the listing for details. Single 1-1/8" Threadless MTB Bike Bicycle Sealed External Bearing Headset Silver. Color: Silver Tone, Condition: New. Listed at 19.99 USD. Description:As the bike headset features a sealed bearing, it guarantees a very smooth performance. And it is rustproof, corrosion-resistant, and impact-resistant.It is the bike headset that is precisely machined to match the main tube of the frame. And it is comfortable to touch for a smooth surface and round edges.Made of aluminum alloy, it is durable.The size of the mounting caliber is 34mm, and the diameter is 28.6mm.It is suitable for being installed on the straight tube fork of a bicycleSpecifications:Color: Silver ToneItem Name: Bike HeadsetMaterial: Aluminum AlloyFeatures: Threadless, Easy to InstallHead Tube: 34 mm / 1.34 inchFit front fork tube diameter: 1-1/8 inch (28.6mm)Thread Size: 1/4-25UNFPackage Including:1 Set of Bike Headset.