Features: Adopting Waterproofs function, it can effectively prevent water and dust from entering the bearing, extending their service life. Make from reliable bearing and metal materials, providing stable operate performances and durability. Featurings a square hole, it is tightly connectings to bicycles base, enhancing stability and transmission efficiency. Comes with Waterproofs screws to enhances the sealing between the center axles and bicycles frame, effectively preventing water intrusions. Suitable for road Bicycles, mountain Bicycles, foldings Bicycles, providing a stable and smooth ridings experience. Specifications: Materials: Metal Size: about 68x127.5mm/2.68x5.02inch Package Includes: 1pc Square Tapered Bottom Bracket note: Please allow 1-2cm errors due to manual measurement, make surely that you not mind before order. Due to difference between different monitors, the picture may not reflect the actual color.