Multiple options in one machine, iCapsol interim cleanings, and deep extraction cleaning. Change from interim to deep cleaning process with the turn of a switch, no mechanical changeover needed. Floating dual counter-rotating brushes agitate and permeate the cleaners into both sides of the carpet nap for even, thorough cleaning and improved carpet appearance. No operator adjustment needed. The DUO machines provide exceptional maneuverability and visibility; their compact design makes it easy to operate in small areas. The deluxe model has chemical tanks which are 1.22 gallon and 0.33 gallon.