1. High speed, low noise, long life 2. High temperature resistance, high precision, excellent products 3. Bearing ring: contains inner ring and outer ring; high quality steel support, high efficiency to extend bearing life 4. Rolling body: transfer the load between inner and outer ring 5. Cage: reduce friction heat, optimize the load, easy to disassemble 6. Integral seal: significantly extend the bearing life, retain the lubricant in the bearing to keep contaminants out of the door 7. Metal sealed bearings: good speed, high temperature resistance, suitable for high-speed operation 8. Rubber sealed bearings: good dustproof effect, suitable for use in harsh environments, dustproof and waterproof 9. Open type non-sealed bearing: good speed, silent, suitable for closed machinery inside 10. Inner diameter: 4mm 11. outer diameter: 13mm 12. width: 6 mm 13. Precision grade: P0 14. Cage and material: nylon cage 15. standard number: CB/T 307.3-2017 16. weight: about 1g/pc