oh my goodness. i bought one of the cutters that close when not in use unless i punch the black button. i cut my thumb years ago and it took a long time for the nerves to stop bothering me. i love my rotary cutter now but i do make sure if i'm using my long ruler, that the side next to the cutter has the guard on it. I'd turned the ruler around and that's how i ended up getting cut! careful is the word of the day.