These are carbide replacement blades for the Smith's Ceramic Edge Pro Electric Knife Sharpener (item #50245). Tungsten Carbide Blades put a quick sharp edge on dull or damaged knives. These carbide blades are precision ground to provide a smoother, more consistent sharp cutting edge on your knife blade. They also sharpen your blade quicker than standard carbide blades. Each of these blades are keyed so that they only go in specific side and only fit a certain way. There is a left side blade and a right side blade, so you will need to purchase both blades for replacement. C11171 is the left side blade. C11170 is the right side blade. Please note, you cannot put the left side blade (C11171) into the right side cavity on the unit, and vice versa. These blades are replaceable only. See additional images for reference to the item that uses these particular carbide blades.

Replacement Instructions: Remove the Phillips head screw(s) and cover over the blades. Save for re-assembly. Remove the existing carbide blades and discard. Insert new carbide blades with sharp edge of grind facing into v-slot. This applies on both sides. Replace the cover and Phillips head screw(s). Tighten screw(s).