[Steel balls]
Bearings
1) Stainless steel ceramic bead bearing
Stainless steel SUS440 bushing, G5 grade silicon nitride SI3N4 ball
Nylon PA66 retainer, low noise grease for synergic motors
Double-sided yellow sealing cover.
2) Bearing steel bearings
Bearing steel GCr15 material inner and outer ring and ball
Nylon PA66 retainer, synergistic SLR grease
Double-sided black sealing cap.