The Hardin Dual Vac System supplied with this set confines both dust and water in a controlled environment. While polishing on site, the need to keep water spray from damaging expensive wooden floors and cabinets can be challenging. Concrete dust can also be difficult to clean and is dangerous to breath. With the Dual Vac System, these damaging and toxic materials are contained and removed by simply hooking up your shop vac. To work with the shroud, simply attach the 6 inch DVS shroud to the wet polisher and attach your shop vac to the 1 1/4 inch vacuum adapter