The Boxxer 423s takes the proven track record of the industry’s top selling truckmount, the Boxxer 421, to an entire new level of reliability, durability, and serviceability. The Boxxer 423S provides more power through increased engine horsepower and improves serviceability by providing easier accessibility to crucial components, including the heat exchanger. The Boxxer 423s has also reduced noise by optimizing airflow with the OPTI-AIR™flow system through the entire machine which provides more consistent heat performance and makes the machine quieter in operation. You can clean everything from the filthiest carpet, to the most delicate upholstery fabric, to the grimiest tile or concrete floor.