Hope this hasn't been discussed before. I did a search but didn't find anything. I kinda learned this the hard way. I bought a used Gascan and it looked like the lenses were smudged so I hit them with the Oakley Lens Cleaner and the thing start flake. Not sure if the guy oiled up the lenses since they were flaking already. Anyways I got stupid and tried to use some auto polish on the lens. Bad move. Polish has some abrasives in it and it scratched the lens. Read where alcohol messes up the coating and since the lenses were already messed up I'd figure what the heck. Soaked the lenses in alcohol and the coating came right off. Today I had a old M-Frame lens which I use while cutting my grass and working outside. It started to flake where the lens touches my cheeks. I was thinking of tossing it since overall it looked really bad. There were little nicks from rocks and stuff getting thrown onto the lens and the coating just didn't look as clear Got a ziplock and put just enough alcohol into the bag to coat the lens. I folded the bag and got as much air out of it and let it soak. I kinda forgot about it and when I came back it didn't look like anything happened but when I pulled out the lens it looked like what happens when you put paint remover on a painted part. It was all wrinkly and lifted off the surface. I rubbed it to loosen the coating and then rinsed it under water with some soap. I was pleasantly surprised. All of the coating came off and it looked pretty good. Note: This was done on a grey lens so I don't know what would happen to a Iridium one but at least I can get more use out of the lens. Especially since it will get more damaged from the stuff being kicked up from my lawn mower.