It is a retractable piercing tool.
I was getting nicked often while poking out die-cut pieces, piercing holes, & pulling up double back tape...so I bought this to avoid that. The only reason I only gave it 4 stars is because it isn't push-button ....but a sliding mechanism which is not smooth in retracting needle. But I'm sure I will get used to it as a tool & save myself a lot of pain & bandages.