The PF4130 central movement is Press Fit into frames with a 41mm diameter and 86.5mm width, and adapts most cranks with a 30mm axle to the standard one. If you have a BB86 frame and want to install a 386EVO crank or a Rotor 30mm crank, this is the kit you need. CeramicSpeed bearings are installed in the cups. The Standard Bearing has CS ceramic balls and hardened steel races. The Coated Bearing has the same balls rotating on hardened steel races with a 3-micron thick metal coating, which makes the races harder and smoother, increasing service life and reducing friction. In the package: 2 cups with bearings installed 2 x 1mm spacers 2 x 0.5mm spacers 2 O-ring dust covers Plastic cable protector Long-lasting grease Decal