The Pentair FullFloXF is a 262512 High Performance Backwash Valve. FullFloXF High Performance Valve has near zero pressure loss across the valve that significantly reduces the amount of energy required by a filtration system. Depending on your utility rates, this valve could save you hundreds of dollars per year when compared to a typical backwash valve. The FullFloXF Backwash Valve easily retrofits to Triton, Quad D.E., FNSPlus, System:3, and System:2 Mod D.E. Filters.