this is a support for lm8uu linear bearing.
you need 6 m3 screw (10 or 16 mm long) and 6 M3 nuts, to connect the support to the y axle.
the left support needs 2 bearing in order to improve the y axle stiffness, hence the plate is more rigid.
I have printed it with PLA and Cura.
layer height 0.2
shell thickness 0.8
top/bottom thickness 0.6
fill density 25%