There is no doubt that our products have high stability, so sliding from the bicycle frame is not easy. Its weight is also illuminated to reduce the burden during cycling, because it has a large area. Naturally, the oxidation process of anode oxidation is adopted, so the surface color is bright and can effectively prevent oxidation and fade at the same time. It is made of aluminum alloy and is durable. There are two sizes to choose from. 31.8mm is suitable for most 27.2-28.6mm seat tubes, 34.9mm suitable for most 30.4/30.9/31.6mm seat Test tube name: Bicycle seat clamping panel: aluminum alloy features: internal shape, ultra-light color, multi-functional details information : Diameter diameter of the seat clip: 31.8mm/1.25 inches (approximately) seat rod end fixture: 34.9mm/1.37 mm/1.37 mm/1.37 (34.9mm/1.37 ") Note: Different from light and screen settings differences The color of items may be slightly different from the picture. Please allow small differences caused by different manual measurements. Packaging includes: 1 X bicycle seat rod clip