1.good wear resistance 2.Good elasticity 3.High precision, high concentricity 4.No bubbles 5.Smooth surface DescriptionPU ... 5A~ 95ATemperatureup to 300°CHub MaterialAluminum, Steel, Sintered Bronze, Brass, Bearing, Many PlasticsBearing ChoicesBall, Needle, Sintered Bronze, PlasticWarranty6 months ... our customers' needs Soft wear resistant PU wheel with axle shaft, High quality (Many hardness)