... precision, high concentricity 4.No bubbles 5.Smooth surface DescriptionPU Roller wheels with aluminum coreBrandKamidMaterialNature rubber, NBR, PU, Silicone...DimensionPer drawing or ... °CHub MaterialAluminum, Steel, Sintered Bronze, Brass, Bearing, Many PlasticsBearing ChoicesBall, Needle, Sintered Bronze, PlasticWarranty6 months ~ 12 monthsSpecial Feature:1. good wear ...