Pentair 25023-0172S D.E. Element Replacement Sta-Rite System 3 SMD-Series Modular Pool and Spa D.E. Filter D.E. element replacement Fits Pentair Sta-Rite System 3 SMD-Series modular pool and spa D.E. filters 72-square feet filtration area Measures 17-1/4-inch length by 28-inch height by 17-1/4-inch width