T47a (asymmetrical) threaded BB cups for T47a frames and 24mm diameter spindle compatible cranks. Cups have internal bearings, and can be used in BB shells with widths from 77. 5 - 79mm. Machined aluminum cups thread together directly into a Cervelo, Factor and Felt T47a BB shell. Bearings are easily serviced or replaced. Includes sleeve to fit between cups for added protection from dirt and grime, and also keeps your internal wires and hoses from rubbing on the crank spindle. T47a BB cups are similar to standard BSA threaded cups in that the drive side cup is left-hand thread and the non-drive side cup is right-hand thread. Use a quality grease when installing in steel or aluminum BB shells, and an anti-seize compound compatible with titanium BB shells. T47 external cup on the drive sideT47 internal cup on the non-drive side