Dirt eraser saves renovating
Have recently tried such a dirt eraser, there's also Master P., I had the "Balbo Power Pad" by Schlecker:
Brilliant! I got rid of the wall, on which mosquitoes, green colored pencils and various abrasion strips of chairs etc. were removed!
And I thought, I would have to delete! I think it's something like chalk in this sponge, so you should not use it on polished surfaces or shiny metal, it may be that they get dull.
