1,The bottom bracket is solid and durable with a long service time. 2,The steel shell can absorb roundness tolerance for installing ports of Bracket Bottom. 3,Integrated System can protect the frame, more power output, it's better than ordinary structure bottom bracket. 4,Suitable for 68mm frame shell. 5,Please use the BB tool to install and replace the bottom bracket for safety. Features: 1. The bottom bracket is solid and durable with a long service time. 2. The steel shell can absorb roundness tolerance for installing ports of Bracket Bottom. 3. Integrated System can protect the frame, more power output, it's better than ordinary structure bottom bracket. 4. Suitable for 68mm frame shell. 5. Please use the BB tool to install and replace the bottom bracket for safety. Specification: Material: Steel Suitable: for 68mm Frame Shell Size: about 68 x 103 or 107 or 110.5 or 113 or 116mm Cups thread size and pitch: 34.798mm 1.37x24TPI Structure: 2 Bearings Package List: 1 x Quare Hole Axis 2 x Screws Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-YJL official store