100mm Zirconia flap discs. Hole size: 15.88mm/16mm (5/8") Flap discs are manufactured in high quality zirconia abrasive. High stock removal on coarse grits, performs well on stainless steel. Zirconia's inherent feature of cooler cutting when grinding makes it a much more durable and hard wearing grain than aluminium oxide and less likely to discolour stainless steel. Manufactured in Europe. Applications: Stainless steel, Normal steels, Alloy steels, Non-ferrous metals and their alloys . Price per 10 discs.