Use these OLFA® blades once, and you'll be hooked. Their hook shape is designed to protect material underneath from being cut. Use these blades for construction materials including drywall, linoleum, carpet, flooring, insulation and roofing materials. Good for applications such as flooring, drywall and roofing repair or replacement. Cuts carpeting, linoleum, drywall, roofing shingles and more.