This headset is suitable for 42mm bike frame head tube, compatible with 28.6mm straight tube steering fork. It can well protect from dust and water, prolong the durability, and all parts are precisely machined.It is the best for your bike. And Durable: High Strength And Corrosion Resistance Double bearing Structure Smoother Than Loose Lighter And Smoother To Turn The Handlebar Rubber Seals The lnterior Has An Additional Seal To Prevent Water And Service Life Colour:black Material:aluminum alloy Size:42MM Package Contents: 1 x Road Bike Headset Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.