These bearings are initially manufactured for Righetti Ridolfi karts and axles, but will work for many karting applications.
Each bearing is complete, with (2) drilled and tapped set screw hole locations for maximum grip on axle.
Depending on your bearing cassette application, the outer diameter of the overall bearing assembly may vary. Because of this, we urge you to consider the dimensions outlined here.
Also, select from different bearing grades: Standard, or RHP (performance)
A standard bearing will wear slightly faster, and may be lower quality than the RHP. The standard bearing is great for cost-effective karting applications, like rental karts or track day karts that will be abused heavily.
The RHP bearing, while pricier, will have a longer service life, and less rolling resistance. This bearing is intended for performance applications.
Each bearing comes complete, with set screws for clamping to axle included.