1、With polished smooth surface, it works well with high efficiency causing low noise. 2、High temperature resistance, able to operate at a temperature range of -20-200℃ or so. 3、Adopting premium carbon steel material, solid enough for a long term use. 4、Wide applications in many fields: industrial machines, cars, ships, household appliances, health care system, etc. 5、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. 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 -20-200℃ or so. Adopting premium carbon 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: Carbon Steel Type: 626ZZ Color: Silver(Shown as pictures) Inner Dia: Approx. 6mm/ 0.23inch Outer Dia: Approx. 19mm/ 0.74inch Thickness: Approx. 6mm/ 0.23inch Application Temperature: -20-200℃ Quantity: 10 Pcs Weight: Approx. 72g Packing List: 1 x 10 Pcs Ball Bearings