Two0 circular rotary replacement blades for Olfa's 45 mm rotary cutters are used for quilting, sewing and general crafts. Tougher than your average blade, these are made of high quality tungsten carbide steel for unparalleled sharpness and superior edge retention. Cuts up to 6 layers of fabric. 45mm Olfa endurance rotary blade, for the RTY-2G, RTY-2DX, RTY-2NS, and RTY-2C rotary cutters, 2 pack.