... concentricity 4.No bubbles 5.Smooth surface ModelRubber BearingBrandKamidMaterialNature rubber, NBR, PU, Silicone...DimensionPer drawing or requestColormore than ... , Sintered Bronze, Brass, Bearing, Many PlasticsBearing ChoicesBall, Needle, Sintered Bronze, PlasticMOQ10pcsPriceBased on dimension & qtyWarranty6 months ~ 12 months 608zz Rubber Bearing, rubber coated bearing (any coating thickness)