Splined bottom bracket for use with Shimano Octalink chainsets.  

The Oversize BB spindle, with a large 22 mm diameter hollow cold forged chrome-moly pipe reduces weight, increases strength and rigidity.

Oversize axle with 8-splines provides a more rigid interface between the crank arm and bottom bracket. 

Fits Shimano FC-M751, FC-M571, FC-M510-8 and FC-M440-8 cranksets.