So, this DOES work, but I would add caveats:If you are trying to remove scratches from a large area, I would definitely order extra green and blue sandpaper pads and source a used car polisher that is plug in.Expect to spend hours using the first two stage polishers. I would NOT recommend using a cordless drill, for a few reasons: it's hard to keep stable, and it will take more hours waiting for the drill to recharge than you will spend sanding, so that's a giant pain..I was trying to use this to sand the inside of a curved tempered glass fishtank with a top portion that was glued on, and made it really hard to get the right angle or apply consistent pressure. And due to this, it was a horrible awful exercise in patience and panic. But I persevered, and after a few days I did see marked improvement in the glassThis totalled to maybe 8-10 hours of total work, but this was partially having to use a drill. I gave up and bought a used car polisher on Kijiji after a day of a drill, and that helped a lot. It would have gone faster if I started with the polisher from the get go.The story: I was refurbishing my fishtank.it had sand in it for a long time, and my hubby was the prime tank cleaner while my son was little, and he would dip the sponge in the sandy water then clean the inside glass. Over a few years of this, I finally realized the entire inside glass had hundreds of scratches all over it. And bad enough that bubbles would stick to them, and algae could grow on them, making it hard to remove (and making him scrub the glass harder)Anyway, I knew it was going to be a horrible pain to attempt to improve, but I decided to try. I only ended up doing 2/3 of the tank. (Ran out of sandpaper, even with an extra order of 5 each of the green and blue stages). Not all scratches are removed, but it ended up being significantly improved on the 2/3 I had done. If I kept at it for another sandpaper order and another week, and didn't care that my forearms were going constantly numb from carpal tunnel, I could have gotten it to about 80-90% improved on the whole tank.But I got to "good enough" and left it at that. The 1/3 of the tank that I didnt do is in the back. Here are some pics- the first shows the scratches, the next few show the improvement and the last is the tank once refilled again after the polishing (another side note- I also got the polishing back to about 80-90%, not 100%. So when the tank is empty there are a few sections that have a minor clouding effect still. I didn't worry about this so much since with water in the tank, the minor clouding wouldn't show. On a clear window it would tho. (But a clear window would be waaaaay easier to polish and scratch remove. I basically tested this on the hardest thing I could possible test it out on. So for that, it's 5 stars, I gave it 4 stars because they really didn't specify you would have to buy more produce if you wanted to do more than get out one scratch..