Best Rust Dissolver for Nuts, Bolts and Screws - Naval Jelly 

Naval jelly is, indeed, terrifically useful. If you let phosphoric acid sit on your skin long enough it will soak into your tissues and kill the cells deeper in your skin & muscles without you knowing it at the time. Symptoms are, hours later, an ache in your fingers like you slammed them in a door. If you're lucky, you get to the emergency room soon enough and they fit you with rubber gloves with an acid neutralizer that soaks your hands & fingers all night, along with direct needle injections into the meaty parts of your fingers every hour. Then you get to keep your fingers. If you are not lucky or wait too long, you don't pay the hospital an arm & a leg, but they do get to keep your fingers as a tip. Wear PPE when handling acids such as this. I'll let someone else harp on the wire wheel fun & games. On the upside, no running angle grinders were juggled in this video.

Please don't use this example. Don't use your bare hands to handle this stuff unless you have no other option. Never use a spinning wire brush with only latex or thin rubber to protect your skin. This video is a hand infection cringe. Chemical burns and metal splinters are all this will provide you with.