Disposable Carbon Steel Surgical Blades, Sklar. Sharp, Curved, Pointed, #12D, Carbon Steel. Sklar's Disposable, Sterile, Carbon Steel Surgical Blade #12D, also referred to as #12B in the United States, is a double edged #12 blade sharpened on both sides of the curvature. It is most commonly used in dental procedures. Disposable blades are available in bulk quantities of 100 per box.