Features: 1. Bearing steel - better quality than common steel, no trouble of repeated installation and maintainence. 2. Metal - stainless steel sealing material can effectively prevent external dust, foreign matters from entering the inside of the bearing which may cause bearing interior damage. 3. High class material - low noise/high accurateness/long lifespan. 4. Wide use - low noise and friction, high running speed, not easy to hot, high load. 5. Durable&reliable - low friction coefficient highly suitable for high speed running. Specifications: Item: 624ZZ Micro Bearing for 3D Printer Type: 3D Printer Accessories Material: Bearing Steel Quantity: 10 PCS Package size: Approx 10*7*5cm/3.9*2.8*2inch Weight: Approx 31g/1.1oz Package list: 10 * 624ZZ Bearings