I use them and they last forever. I am always, always cutting kits for Project Linus and don't have a dull one yet. Many buy the single packages but when those are gone, I buy the package with the cutter in them and it comes with 3 blades for 3.99. Yes there are other threads on this but different people come on different times, and this is how we share. It takes wayyyyyyyy too long to always search for a subject. Just saying...... :)