The ACCUTRAX Pencil Blade is the ultimate carpenter"s pencil, it"s a pencil not a razor that can be inserted into your utility knife. Designed to fit in all standard utility knives, any razor blade can be swapped out for the ACCUTRAX Pencil Blade. Just insert the Pencil Blade in place of a razor blade in any standard utility knife and it"s ready to go. Sold in set of 3.