Each setcontains 3 diamond coated hone blocks. These hard, sharp, tough, stones are available in various grits. Recognized for the clean, sharp surfaces they produce on tools, dies, blades, molds and almost any other metal piece requiring sharpening or smoothing. Each measures approximately 6" x 2" (152 x 51 mm). Each set contains: One blue coarse 150 grit block One red medium 300 grit block One yellow fine 450 grit block Newer versions of the item shown may be shipped, as a result, there may be a slight variation in color and design.