Ceramic deep groove ball bearing ZrO2 16019 Compared with steel ball, Si3N4 ball has following advantages: 1 .23%lighter than steel ball, which means less centrifugal force and less friction on the groove during high speed and acceleration. 2.Smaller fiction coefficient, more freely rolling. 3.Can be used at higher temperature up to 800°C 4.Never rust, and can roll with out lubrication. 5.More corrosion resistant than steel 6.No metal contamination. 7.Non-magnetic 8.Electric isolation