Three, sealed cartridge style, bearings; two on the chainring side and one on the non-drive side.Weighs just 220 grams; only 30 grams more than Record.17 mm cro-moly steel, 102 mm hollow spindle fits 8, 9 and 10 speed Campy Record and Chorus cranks from 1995 to present.Unique taper is not interchangeable with Shimano.Removable cups are machined from 7000 series aluminum alloy and are easily replaceable.Comes with British (1.37 inches x 24 threads per inch) or larger diameter, Italian cups (36 mm x 24 threads per inch). Spindles are identical and always 102 mm long..