608-ZZ Ball Bearing, this is a popular size of Skate bearing or any application that uses this size 8mm x 22mm x 5mm. Bearing is made of Chrome Steel, also bearings are Oil lubricated to be smooth. Item: 608-ZZ Ball Bearing Type: Deep groove ball bearing Material: Chrome Steel Lubrication: Oil Dimensions: 8mm x 22mm x 5mm/Metric ID (inner diameter)/Bore: 8mm OD (outer diameter): 22mm Width/Height/thickness: 5mm Size: 8 x 22 x 5 mm Package Included: 1 pcs 608zz