These are 2 pairs of default bushings come along with WRA-012 FlyWheelz™ 5"-130mm Eight Spoke PU Wheels. The bushing internal diameter: 5mm and 6mm, suitable for 5mm and 6mm wheel axle.
 
We upload this product because sometimes someone will lose this little thing, not because it is easy to damage. In fact, we hardly heard that it has been damaged. These bushings are CNC machined from high hardness plastic material.
 
Note: These products are in stock in US warehouse now, you can choose US warehouse shipping.