Features1Composed of high quality carbon brazing material, which is durable, light in weight, high in strength and toughness. 2Full carbon fiber stem washer inner diameter about 28.6mm/1.1in (universal fork tube specification), suitable for 28.6mm/1.1in front fork. 3Provides a variety of combinations to adjust the height of the handlebars to suit the riding style, having an riding experience. 4Easy to install and use. The washer makes it very easy to adjust your bike stem and helps to raise your handlebar. 5This bicycle headset spacer is wear resistant, corrosion resistant, rhombuses bumps on the surface are easier to prevent slip.SpecificationItem Type: BicycleHeadsetWasherMaterial: Carbon Fiber4pcs: Inner Diameter: Approx. 28mm / 1.1inOuter Diameter Approx. 34mm / 1.3inHeight: Approx. 3mm //0.1in 5mm / 0.2in 15mm / 0.6in 20mm / 0.8in5pcs:Inner Diameter: Approx. 28mm / 1.1inOuter Diameter Approx. 34mm / 1.3inHeight: Approx. 3mm /0.1in 5mm / 0.2in 10mm / 0.4in 15mm / 0.6in 20mm / 0.8in(the quantity is based on your choice)Package List4 xWasher