Features: Good quality: This product is made of high-quality materials, exquisite workmanship, very good quality and long service life. Easy installation: This product is very easy to install, no additional tools are needed, and the installation process is very convenient. Appearance matching: The appearance of this product is verymatches, and there will be no sense of violation after installation. Beautiful: This product is made with functional exquisite craftsmanship, and appearance is very stylish and beautiful. Portability: This product is small in size and light in weight, which is very convenient to carry around. Specifications: Material:Alloy Type:1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9 or 10 1:Approx.32mm or 1.26inches 2:Approx.25mm or 0.98inches 3:Approx.36x16mm or 1.42x0.63inches 4:Approx.36x14mm or 1.42x0.55inches 5:Approx.30x10mm or 1.18x0.39inches 6:Approx.30x12x9mm or 1.18x0.47x0.35inches 7:Approx.30x9x12mm or 1.18x0.35x0.47inches 8:Approx.30x8x10mm or 1.18x0.31x0.39inches 9:Approx.36x9x12mm or 1.42x0.35x0.47inches 10:Approx.30x8x10mm or 1.18x0.31x0.39inches Note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes: 1x Gear Sprocket