There's a shop item that looks like a Mask of Lorenzo, It says it blocks bullets, but says so in a very 'scammy' manner. I want to know what it does before I buy it because I haven't found a way to remove items or modifiers from my run and I'm pretty far in.

Maybe what they said was true.....?

I mean, why not buy it and give it a try, all you need is some gold!

If you're really worried... You can back up the game save before you buy it.