Olfa Ultra-Max Standard Duty Snap-Off Blades: Premium black blade ideal for applications requiring superior sharpness. Exclusively designed for maximum cutting performance, are ideal for applications where superior sharpness is required. These blades made from high quality carbon tool steel are developed using a "special" double honing process for extreme sharpness and are 25 percent sharper than our Standard-Duty AB blades. Long lasting durable snap-off blade - a new sharp edge with each snap. Fits most Standard-Duty handles. 8 cutting edges per blade. 50 blades per pack.