【double shielded】They are double shielded to avoid contaminants entering and save lubricant can also extend the service life. 【696ZZ】 Bearings have 6mm inner diameter, 15mm outer diameter and 5mm thickness. 【high quality steel】These mini ball bearings are made of high quality bearing steel for low noise and long service life. 【10pcs】There are 10pcs mini bearings in one set which you may use for many different projects. 【wide applications】 These are great for small hobby 6mm shaft/rod projects. Can be used for medical apparatus and instruments, cryogenic engineering, optical instrument, high-speed machines., Weight: 0.0881849048 pounds, Manufacturer: Hilitand