Rotor UBB 4630 Steel Bottom Bracket"The motive for the UBB 4630 was to address challenges related to bottom bracket installation and durability with specific frames," said David Martinez, head of engineering at Rotor.The UBB 4630 Bottom Bracket uses a threaded sleeve that locks both cups in place, increasing the stiffness of the bottom bracket shell. It also eliminates one the most common and frustrating issues with pressfit bottom brackets, creaking, while ensuring free and smooth spinning cranks. As perfect alignment is achieved, you can expect longer bearing life and the sleeve prevents cables and guides rubbing against moving parts.Features: Material: 7000 series Aluminium Threaded installation Weight: 109gBuy Rotor Components from Chain Reaction Cycles, the World's Largest Online Bike Store.