Rotor BB30 To 24mm Steel MTB Bottom BracketOur ingenious BB30 to BB24 converter BB which allows the installation of conventional BB24 cranks in BB30 frames. Using our new, non-contact labyrinth seals, Rotor has been able to achieve a buttery-smooth feel along with unparalleled protection against dust, water and mud.Available only with steel bearings, in black. Available only with ceramic bearings in red. Compatible with all conventional BB24 cranks manufactured by ROTOR, Shimano and Shimano-compatible brands. Available in both Road and MTB sizes, weighing 118g for road and 120g for MTB.Features: Threaded interface ensures perfect bearing alignment, provides airtight seal from frame contaminants and allows for self-installation /extraction. Steel (black) 122.5g, Ceramic (red) 114.8g. T6 heat treated 7075 Aluminium cups. For all ROTOR and Shimano compatible 24mm cranks.Buy Rotor Components from Chain Reaction Cycles, the World’s Largest Online Bike Store.