[Zirconium Oxide Discs] The high quality real zirconia abrasive grains are attached to the surface of the abrasive cloth by electrostatic sand planting, strong cutting force and long service life. [Aluminium Oxide Discs] Thick D-weight Aluminum oxide sandpaper is bonded with thicker blue cloth backing, more glue added, making the sanding disc much more durable.
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