Double lock design, thread lock, enhance the stability of the bottom bracket and prolong the life of the bottom bracket High-quality aluminum alloy material, light and durable, with built-in/external bearing bottom axis to choose from Five-way: Internal application: 86/92mm External application: 68/73mm Internal diameter 24mm/0.94inch, stable rotation, easy installation and operation Colour: Black. Weight: about 113 grams Specification: Material: Aluminum alloy Size(L): Approx. Internal: 85mm/3.35inch external: 88mm/3.46inch Package Includes: 1 Piece Bike Bottom Bracket Note: Color might be slightly different due to the color calibration of each individual monitor. Please allow slightly measuring deviation due to manual measurement.