Hyde Tools 42345 Retractable Snap-Off Knife Replacement Blade, 9mm, 5-Pack 9mm blades are great for cutting cardboard, foil, paper, wall covering and more Package contains 5 blades, with 13 sharp points per blade. To refresh the blade, simply snap off the point to reveal a fresh one. No tools required All Hyde snap-off knives have built-in blade breakers for added convenience