Constructed entirely of Stainless Steel and Teflon™ and used with a Pollution Recovery Motor and continuous Teflon Motor Lead, the Redi-Flo 4” pump is the perfect pump for constant speed pumping of groundwater contaminated with petroleum hydrocarbons or other contaminants. Add a Grundfos Variable Frequency Drive and Variable Speed Motor, and now you have an environmental pump that has flow ranges from 100 ml/min. to 50 GPM and head capacities up to 590 ft.