McKee 37 Hi-Intensity APC. Used a 10:1 mixture on my friends car, which was a 2007 Mazda 3. I've heard that the Mazda 3 carpets are a bit tough to work on and his carpet was covered with about five or six winters worth of road salt. I sprayed the crap out of the salt that was caked on and scrubbed it. Took an hour but it was extremely good at getting the salt out. I was probably able to get out almost all of it since it was just a scrub brush and the APC, no extractors or steam cleaners. That and the McKee Interior cleaner was great on the rest of his car for cleaning anything and everything. This was a car that has not been properly detailed since he got it brand new, just wiped down every so often.