This Large Flattening Stone is your key to restoring your whetstones, oil stones, and water stones to peak performance. Dual-Grit Precision for Any Stone: Whether you're working with a coarse sharpening stone for knives or a fine-grit honing stone, this dual-grit flattener has you covered. The coarse #120 grit side quickly tackles uneven surfaces and repairs damaged stones, while the fine #320 grit side provides a smooth, polished finish for optimal sharpening results. Extra-Large Surface for Effortless Flattening: Say goodbye to tedious, time-consuming flattening. This extra-large flattening stone boasts an expansive 8 in. x 3 in. x 1-3/16 in. surface area, making it significantly larger than most competitors. Effortlessly flatten even the largest whetstones, water stones, or oil stones with ease. Innovative Diamond Grooves: The unique diamond-shaped grid pattern isn't just for show. These grooves efficiently channel away waste material during the flattening process, ensuring a clean and even surface on your sharpening stone. Long-Lasting Performance: Crafted from high-quality silicon carbide, this flattening stone delivers exceptional durability and cutting power. Quickly and effectively re-level your sharpening stones, extending their lifespan and optimizing their performance for years to come.