Item Type: 608ZZ Ball Bearing Material: Carbon Steel Inner Diameter: Approx. 8mm / 0.31in Outer Diameter: Approx. 22mm / 0.9in Thickness: Approx. 7mm / 0.28in Weight: Approx. 92g / 3.2oz Package List 8 x Bearing 1Carbon Steel Material: Made of high quality carbon steel, high hardness, heavy bearing capacity, smooth surface and corrosion resistance. 2ABEC 11 Bearing: Using ABEC 11 standard specification bearings, high accuracy, low noise, uniform speed during high efficiency operation. 3Good Performance: 608ZZ ABEC 11 bearing has stable performance, good coordination with machinery, and improved work efficiency. 4Wide Range of Application: 608ZZ ball bearing can be used for twisting cars, roller skates, dance boards, skateboards, etc. 5Wear Resistant: Bearing are resistant to wear during high speed operation. Metal cover sealed to prevent the entry of impurities.