Stauff RF Return-Line Filters are designed as tank top filters. They are mounted directly on the tank top and when 100% of the systems oil is filtered they provide the optimum removal of contaminant from the system. This provides the pump with clean oil thus reducing contaminant generated wear. The filter bowl is designed to return the oil beneath the surface thus preventing the entrainment of air by the returning oil. A high efficiency of contaminant removal is assured by using Stauff RE Replacement Filter Elements. The high dirt-hold capacity of Stauff elements ensures a long service life and as a result, reduced maintenance costs. NOTE: STAUFF RE FILTER ELEMENTS ARE DESIGNED FOR USE WITH STAUFF RF FILTERS.