The Singer 45 mm Rotary Cutter Pro Series 6-Pack Replacement Blades are designed to fit the Singer Rotary Cutter Pro Series model # 07179 and works with most other brands of 45 mm rotary cutters. The replacement blades are razor sharp and provide precise cutting of materials such as denim, fabric, cardboard, paper and felt. Each package contains (6) high quality razor sharp replacement blades and comes with a convenient reusable plastic storage container to keep blades clean and sharp which provides for prolonged blade life.