Review on Sungold Abrasives 8150599 Silicon Carbide by Deep Echemendia

I was expecting 220 grit to be 220 grit but I tried using these shims between polyurethane layers for hardwood floors (as they should) and it left deep scratches. Created a nightmare that I need to fix. Deep scratches weren't everywhere either, just in a few places, as if large particles had stuck to the disc that shouldn't be there. And yes, I make sure there is no dirt or foreign objects on the pillow. And my floors were perfectly clean before I started. I used 2 disks and got the same result with both, and the disks said "220", so there is no error here. Anyway after ruining my floors with these discs I went back and used 220 grit sandpaper just to see and 220 grit sandpaper gave me the smooth result I was expecting from these discs. So be careful buyers, I would NOT use them between layers of resin. Either I got a bad batch or these things are just junk, like 220 grit, more like 80 grit.