The Ultra Sharp 3000 Grit is is an extremely fast honing diamond sharpening stone. Although it is an extra fine grit it leaves a razor sharp edge on all knives and tools. The Ultra Sharp 3000 Grit will easily sharpen high carbon, stainless steel, and ceramic knives! The Ultra Sharp 3000 is made of micronized monocrystalline diamonds electroplated onto a solid steel plate. It is considered to be a finishing stone and provides an excellent finished edge for most sharpening applications. Like the lower grit Ultra Sharp stones, it removes steel at a very fast rate. We have never seen another stone remove steel as quickly yet still leave such sharp edge. We've tested every diamond sharpening stone made and the Ultra Sharp performs as well or better than any of them. We're so confident in these stones that we back them with our "No Questions Asked 100% Satisfaction Guarantee"! Simply return the stone to us and we'll either replace it or give you a full refund whichever you prefer. No questions asked.