APPLICATION-- Precision bearing fits for the rail track system. Suitable for 3d printers, mobile doors, glass sliding doors, aluminum doors and window, pulleys and drawers, wheelbarrows, garden carts, etc.ABOUT THIS PRODUCTS- Single-row, pre-lubricated, ABEC1 accuracy.- Both sides are shielded to keep lubricant and protect from dirt and debris.- Bearing steel races, high hardness, and great wear resistance, showing stable performance and lasting service life.
eBay