The ITA30 bottom bracket kit is an impressive bit of design. It allows you to mate a 30mm spindle crank, like those from Rotor to a narrow 35mm diameter, 70mm wide threaded bottom bracket shell.
The bearings come installed in cups, which are then threaded into the bottom bracket shell. Those bearings are either our Standard or Coated Bearings. Both have super round, super smooth CeramicSpeed balls rolling on hardened-steel races. The Coated version has a metallic coating laid onto the races, making them even harder and smoother, resulting in longer life and lower drag.