Shimano's V1 compatible octalink bottom bracket. Recommended for V1 spline-compatible cranksets only. Not compatible with V2 or ISIS splined systems. Compatible with splined V1 Shimano Dura Ace®, Ultegra®, 105® and XTR® 22mm 8-splined hollow systems. Large diameter pipe billet spindle. Sealed Cartridge bearings. Splined spindle ends for increased joint strength.