customer replaced windows in house and dropped a mess of spray foam ins on the hallway in his home when i got there it was a large yello stain about 10-12 inches around on the carpet .he told me he was gonna use ACETONE to remove this what i thought was a permanent stain,no way i thought ,he worked on that spot the whole time i was there he asked me to clean the spot and i could not see it ,it was gone atleast 98 percent i was shocked .he told me this spot is gonna come out and thats that.he showed me ....