Oversize BB spindle - large 22 mm diameter hollow chrome-moly pipe billet spindle reduces weight, increases strength and rigidity
Octalink splined axle/crank arm interface - results in more rigid crank assembly compared to square tapered spindle
Sealed cartridge assembly - maintenance-free sealed cartridge keeps out dirt, mud and water
Buy Shimano ES30 Octalink Bottom Bracket from Chain Reaction Cycles, the world's largest online bicycle store.
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