RAZOR SHARP 25mm SAW BLADE - Our saw blades are made from carbon tool grade steel for unparalleled sharpness and superior edge retention. The serrated blade provides powerful teeth-edge cutting power. They allow you to work longer uninterrupted. CONTAINS 1 EXTRA HEAVY DUTY BLADE - Each refill pack contains 1 serrated steel blade for cutting tough materials. Be prepared for your next cutting task with these ultra-sharp utility knife blades. COMPATIBLE WITH 25mm KNIVES - OLFA's HSWB-1/1B Saw Blades are compatible with any 25mm precision/utility knife. However, these blades perform best when equipped with a 25mm OLFA knife. CUTS A VARIETY OF MATERIALS - This replacement blade provides accurate and reliable performance when cutting thick materials like leather, rubber, rope, fiberglass, acetates, and more. Great for industrial use, construction, or other heavy duty jobs. THE OLFA STANDARD - As the original inventor of the Snap-Off Knife, OLFA has maintained a standard of cutting excellence for our quality and durability. Pairing your OLFA 25mm Utility Knife with OLFA 25mm Blades will provide optimal results.