Features: With polished smooth surface, it works well with high efficiency causing low noise. High temperature resistance, able to operate at a temperature range of 0-120 or so. Adopting premium bearing steel material, solid enough for a long term use. Wide applications in many fields: industrial machines, cars, ships, household appliances, health care system, etc. With 10 pcs in package, you can keep them for spare or just substitutes for those old ones, all is okay. Very practical in our daily life. Specification: Material: Bearing Steel Type: 698ZZ Color: Silver(Shown as pictures) Inner Dia: Approx. 8mm/0.31inch Outer Dia: Approx. 19mm/0.74inch Thickness: Approx. 6mm/0.23inch Working Temperature: 0-120 Quantity: 10 Pcs Weight: Approx. 70g Packing List: 1 x 10 Pcs Ball Bearings Package List 1With polished smooth surface, it works well with high efficiency causing low noise. 2High temperature resistance, able to operate at a temperature range of 0120 or so. 3Adopting premium carbon steel material, solid enough for a long term use. 4Wide applications in many fields: industrial machines, cars, ships, household appliances, health care system, etc. 5With 10 pcs in package, you can keep them for spare or just substitutes for those old ones, all is okay. Very practical in our daily life.