McKee's 37 Carpet Extractor Pre-Treatment makes your hot water extractor work even better! McKee's 37 Carpet Extractor Pre-Treatment is a non-foaming formula that emulsifies carpet and upholstery stains and then encapsulates soil for easy removal. This non-sticky, pH-balanced formula does not leave a residue on carpet or upholstery. The fast-acting cleaner is completely biodegradable. No dilution is required. Spray it on and stains will disappear.