Sharpen the edges of youe steel blades & tools with Magnusson Sharpening stone Magnusson Sharpening Stone, SF51 features diamond grit material Magnusson Sharpening Stone consist of low-carbon steel, plastic & polypropylene (PP) materials Magnusson Sharpening stone comes in 60 g weight with 15 x 5 x 0.38 cm size