Shiny Nickel coating enhances rust and corrosion resistant. Steel hubs are soldered with the cast-iron core so it is hard for dust, water and silk to intrude the ball bearing and shaft. Thus lessen the needs for maintainance.
Carefully Zinc coating enhances rust and corrosion resistant. Apply the new Steel core PU wheel - the caster look quite strong but still elegant. The quality is assured as it is made by number one caster manufacturer of Viet Nam.