These are new upper and lower bearings for the bearing carrier provided in the belt drive kit. The bearing carrier replaces the stock drive gears. The stock bearings will work just fine, but can sometimes be quite difficult to remove from the stock drive gears. And require a gear puller. This alternative is reasonably priced and will save you time and aggravation during the installation process.
The lower bearing is a 6007 62mm x 35mm x 14mm
The upper bearing is a 6209 85mm x 45mm x 19mm
These are not spindle bearings. These replace the stock drive gear bearings.