The bottom bracket is solid and durable with a long service life. The steel shell helps absorb roundness tolerance during installation of the bottom bracket ports. The integrated system design helps protect the frame and delivers improved power transfer compared to standard bottom bracket structures. Compatible with 80mm and 100mm frame shells. For safe installation and replacement, use a proper BB tool. Specifications: Condition: Item Type: Bicycle Bottom Bracket Material: Steel Color: Black Compatibility: Designed for 80mm and 100mm frame shells Cup Thread Size and Pitch: 34.798mm, 1.37" x 24 TPI Available Styles: 80x142mm, 100x155mm, 100x177mm Dimensions: Approx. 80 x 142mm (3.1 x 5.6"), 100 x 155mm (3.9 x 6.1"), 100 x 177mm (3.9 x 7.0") Weight: Approx. 384g Package Includes: 1 x Bottom Bracket with Screws