Oster Cryogen-X Pet Clipper Blade, 4.70 x 3.50 x 11.75 inches Oster Cryogen-X blades are made using a 12 step process that ensures superior Cutting quality The size 4F blade leaves the coat 3/8 Inch without the need for a guide comb Patented Cryogen-X process take the blade to -300 degree F for extra hardness Hand lapped for a smooth cut finish Handcrafted in the USA