Size: 40 The size 40 Oster Detachable Pet Clipper Blade is designed for extremely close clipper work, making it a great choice for clipping ears and foot pads on dogs or clipping over eyes or muzzles on horses. This detachable clipper blade cuts hair down to 1/100 inch, which means it can also be used as a veterinary surgical prep blade. Oster metal clipper blades are handcrafted to rigorous standards and then sharpened, finished, and tested using Oster's proprietary processes to ensure exceptional sharpness and durability. This metal clipper blade can be used under Oster universal comb attachments and fits a wide variety of Oster clippers. Oster Clipper Blades are manufactured in the USA with superior craftsmanship and pride for reliable results groom after groom.