Flawless Precision: Proudly made in the USA, each lapping plate is hand-certified and guarantees to be flat to less than 0.0005 inches, or 120 microns, ensuring incredible precision when flattening sharpening stones, getting you back to sharpening quicker Effortless Flattening: With an expansive size of 10" long x 4" wide, our diamond flattening stone provides a surface area of 40 square inches. Perfect for flattening both small and large stones, while a grooved surface minimizes suction Long-Lasting Durability: Featuring a revolutionary Hardcoat technology, this lapping stone is designed to provide years of reliable performance, making the diamond lapping plate an essential in any toolbox Consistent, Even Coverage: These precision-ground, 95 micron diamond sharpeners are designed to deliver an even coating of micronized monocrystalline diamond, restoring flatness to your favorite knife sharpener Keep Your Stones In Top Shape: Effortlessly bring back flatness to any sharpening stone including waterstone, oilstone, or Arkansas stone. Trusted by professionals, the diamond lapping plate is essential for maintaining perfect sharpener flatness