6061 CNC machined Alloy cups w/ Precision sealed bearings.
- Bearings: 19mm mid sealed (x2) (with american cups)
- Spindle: 19mm, 8 spline (included in kit)
- Spacers: 6061 Alloy cones with 15/16"/19mm hat washer and 4x spacers included
NOTE: These sealed American BB & American BB sealed upgrade kit (with 8-spline spindle) are designed to replace the 8 spline spindle and bearings of an unsealed American BB with a sealed version. Fits most complete bikes that come with unsealed American 19mm BB. 19mm Model does not come with a spindle.