I had a finger chopper over 50 years ago and it was a high quality device. Made of metal (unlike the transparent ones I bought for my grandchildren from you folks) so no one saw how the blades were rotated. Of course back then we (budding magicians) were expected to practice and use common sense so the there was a very sharp blade on one side. You could chop two carrots cleanly for openers then set the chopper and place your finger in the upper hole and a carrot in the bottom hole. SLAM your finger (or volunteer's from audience) remained complete without a mark while the carrot, string bean or even cigarette was cleanly cut. Very impressive and as a teenager it was a great trick to own. Very disappointed with the ones I bought/

This is mainly good to use on yourself to prank people. In order for the trick to work, you have to put your finger in the large hole and pull up. The problem is that it doesn't stay up, so if you want to get an audience member to put their finger in, you can't let go of the handle, or it will drop and likely reveal the trick to the audience. For this to make sense in performance, one would really need to be able to let go of the handle without the high likelihood of revealing how the device works. Once could potentially work pulling the "blade" up through one's finger as part of the performance, perhaps to prove that it's safe, but that's about the only solution to the problem that I can see.

The best way to use this is to repeatedly "slice" it through your own finger. You have to do it quickly even then or any witnesses would likely see the "blade" moving.

This might be fun to use with blood capsules or in lieu of fidget-spinners for kids with darker senses of humor. For $3.50, I'm not complaining.

If you're a toy collector, I should note that mine came in a reclosable bag rather than carded as in the picture.

I had always wanted one of these as a kid, and it was cheap enough that my expectations were low. It's fun for a few minutes when you're in the mood, but I wouldn't recommend it for a performer.

and it sucks