Cassette Body: 10 speed Hub Spacing: 130mm Spoke Drilling: 28, 32 or 36 hole Weight: 264 g.
While the grade of materials and the surface treatment of the races may change between groups, one thing is constant. Shimano hubs exclusively use a cup and cone bearing system in all of its hubs. Cup-and-cone bearings offer greater strength than sealed cartridge bearings due to their ability to displace lateral and vertical loads more effectively for super smooth rotation in real world riding conditions.
Cup-and-cone bearings also allow for easier maintenance, adjustability and serviceability.