This bearing has Two Metal Shields (ZZ), Non-Connected to the Inner Ring to Protect the Bearing from Dust or any Possible Contamination. Bearing is Pre-Lubricated with High-Quality Grease ideal for use in High and Low-temperature settings (-20C to +160C). If your Application Requires a Ball Bearing with One Shield or Opened Without Shields, you can easily remove one or both Shields. - Specification: Item 6006-2RS, Series 6000, Inner Diameter 30.00 mm, Outside Diameter 55.00 mm, Width 13.00 mm, Dynamic Load Rating Cr 13800 N, Static Load Rating Cor 8300 N, Limiting Speed 8000 r/min, Clearance Normal, Tolerance Inner Ring 0 to -12 μm, Tolerance Outer Ring 0 to -13 μm, Tolerance Classes P0, Noise and Vibration Z1V1, Closures Two Rubber Seals (2RS), Lubrication Type Grease Shell RL2, Lubrication Temperature -20°C to +160°C, Rolling Element Indicator Ball, Material Gcr15, Product Weight 0.120 KG.