8mm Bore Bearing with OD: 40mm Plastic Tire 8x40x10mm Round Type for Sliding Doors8mm Bore Bearing with 40mm Plastic Tire Wide 10mm Round Type 8mm x 40mm x 10mm Steel Ball Bearing with a Plastic tire Combined plastic tire with a 8mm inner diameter ball bearing, dimensions are 8x40x10 Item: Tire combined with a steel ball bearings Type: Tire combined with a steel ball bearings Standard: Metric Size: 8mm x 40mm x 10mm Inner diameter (Bore): 8mm Outer diameter: 40mm Tire Width: 10mm Quantity: One Bearing