Features: 1. These miniature bearings are made of high quality bearing steel for durability and long service life. 2. There comes total 10 pieces miniature bearings which you may use for many different projects. 3. Features smooth operation, small error, low noise, high speed. 4. High precision, stable performance, long life and high reliability. 5. Widely used in electrical machinery, power tools, sports equipment, packaging machinery, food machinery, printing machinery, engraving machines, automation equipment, CNC equipment, and so on. Specification: Condition: 100% Brand New Item Type: Linear Motion Bearing Material: Threaded Rod End Joint Bearing Quantity: 10pcs Optional Size: M3, M4 M3 : Threaded rod inner diameter: 3mm Threaded rod length: 15mm Bearing inner diameter: 3mm Bearing outer diameter: 12mm M4 : Threaded rod inner diameter: 4mm Threaded rod length: 15mm Bearing inner diameter: 4mm Bearing outer diameter: 14mm Package List: 10 * Bearings