The Expert QD-3500 combines all the features/ benefits of the SP-3000, but, comes with a compressed air nozzle/trigger mechanism. This allows you to clean and dry using one hand. Great for use with spot cleaning stations. FEATURES: Has all of the features of the SP-3000 Air nozzle allows you to clean and dry simultaneously. Sleek modern design Operates on electricity and compressed air (for air dryer).