Shimano ES300 Octalink Bottom Brackets. This Octalink bottom bracket is a direct replacement for the ES25 and designed to be used with Shimano Octalink chainsets. Octalink splined axle/crank arm interface results in more rigid crank assembly compared to square tapered spindle.

Key Features

• Oversized BB spindle - large 22mm diameter hollow cold forged 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 with oversized ball bearings - maintenance-free high efficiency rubber seals keep out dirt, mud, and water
• Cartridge design allows easy installation without adjustment
• BB Shell Width: 68mm and 73mm
• BB Thread Type: English
• Spindle Interface Type: Octalink V2
• 9mm Spline length

ISO threaded internal

BB shell inner diametre:- 1.37in x 24 TPI
Bearing inner diametre:- N/A, internal BBs have integrated spindle
BB Shell Width:- 68mm Road, 73mm Mountain & 83mm Downhill 
Installation:- Threaded internal bearings
Compatibility:- Octalink V2 - 9mm
Other names:- BSA or BS threaded
Other notes:- Bottom bracket must be spec'd with correct shell width and spindle length