FEATURES: 6061 CNC machined Alloy cups w/ Precision sealed bearings.

BEARINGS: 19mm

SPINDLE: 19mm, 8 Spline

SPACERS: 6061 Alloy cones w/ 15/16"/19mm hat washer and 4x spacers included 

NOTE: These sealed American BB & American BB sealed upgrade kit (w/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.