4″ Black Buff Dry Diamond Polishing Pads are Hook and Loop backed perfect for Marble, Granite, Concrete, Stone, Quartz, Slate, Tiles, Terrazzo, Engineered Stone etc. This design is much more flexible to flex around concave and convex surfaces. Great or polishing flat surfaces and beveled edges. Aggressive and Durable made with quality Diamond Powder impregnated in Resin. Flexible Hook and Loop Backed and 3 mm Thickness, dry applications. 3mm thick for long life. 1 Pack.