Bearing:

a). 52100 Chrome Steel;

b).AISI440C or AISI420 Stainless Steel;

c). ZrO2 Ceramic w/Si3N4 balls.

Pillow Blocks:

a). Insert bearings can be 52100 Chrome Steel, or Stainless Steel;

b). Housing can be HT200 Cast Iron, 304# Stainless Steel, or ABS Thermoplastic. 

Main Body:

a). C45 Steel;

b). Alloy Steel;

c). Stainless Steel;

d). Customization.