If it's precision you want, choose these OLFA® snap-off blades. They are extremely sharp to begin with, and you can snap off a dulled edge to maintain cutting precision. Use these blades for construction materials including drywall, linoleum, carpet, flooring, insulation, and roofing materials. Made from high-quality carbon tool steel Double-honed blade provides superior initial sharpness and edge retention Exact 59 degree edge angle optimizes cutting power and minimizes blade breakage