This is the bottom bracket you need when using Dura Ace 7710 track crank arms on an Italian track frame having a 70mm shell with right-hand threading on both sides.

70mm Italian threaded (1.370″ x 24 tpi – both cups right-side thread)

spindle: 109.5mm Octalink

sealed cartridge bearings

crank arm bolts & dust caps sold separately

requires Park Tool BBT-22 & any track lockring tool for installation & removal

weight: 173g