Description: Miniatureball bearings are available ball bearings of small size. These miniature ball bearings have a 8mm inner diameter, a 16mm outer diameter, and a 5mm thickness. Ballbearings of this size are ideal for precision work and applications that require a lot of functional mechanical parts, suchas mechanical equipment, electrical instruments, toys, doors and windows. Features: These miniature bearings are made of high quality bearing steel for low noise and long service life. They are double shielded to avoid contaminants entering and save lubricant. Bearings have a 8mm inner diameter, a 16mm outer diameter, and a 5mm thickness. These are great for 8mm shaft/rod projects such as mechanical equipment, electrical instruments, toys, doors and windows.There comes total 10 pieces miniature bearings which you may use for many different projects. Specifications: Material: Bearing steel Inner Diameter: 8mm / 0.31"Outer Diameter: 16mm / 0.63" Thickness: 5mm / 0.19" Quantity: 10pcs Package Includes: 10 x Bearings .