Boxxer 421 The Boxxer 421 offers big-machine performance at a small-machine price. It features incredible heat that can be fine-tuned to clean everything from delicate upholstery to the dirtiest of carpets. Plus, it does a great job on tile, grout and other hard surfaces. It’s excellent for extended flood extraction, too. Even better, the Boxxer 421 was designed to require very little maintenance and is therefore economical to operate. No wonder it has been the industry’s top-selling truckmount for many years.