Splined bottom bracket designed for use with shimano road octalink cranksetoversize bb spindle large 22 mm diameter chrome moly hollow pipe billet spindle reduces weight increases strength and rigidityoctalink splined axlecrank arm interface results in a more rigid crank assembly compared to square tapered spindlemaintenance free sealed cartridge design prevents corrosion and is easy to installaluminium adapteraverage weight 250 grams