Dura-Ace Track<br /><ul> <li>OCTALINK Splined BB Interface</li> <li>Compatibility FC-7710 </li> <li>Hollow Pipe: Yes</li> <li>Axle Length: 109.5mm</li> <li>Shell width: 68mm(BC1.37) (English)</li> <li>Weight: 260g</li></ul>