These sanding discs feature a ceramic, closed-coat abrasive and a premium cloth backing that helps them last up to 10 to 20 times longer than similar discs on mild steel, high alloy, and stainless steel. They feature PSA (pressure-sensitive adhesive) backings to enable quick disc changes. The 3X Performance coating offers improved performance when working with soft metals and aggressive applications, including weld, flash, and gate removal.