The Hayward Perflex Extended Cycle DE Filter sets the standard for crystal clear swimming pool water. A diatomaceous earth filter is the most effective filter media available to pool owners. Use this filter to remove even the smallest of particles that could potentially cause problems for pool surfaces and equipment. Between the long lasting Extended-Cycle filter cycles, DE filter media, and Flex-Tube design, there is no other filter that can compare to the level of clean that this filter design can provide.
| Model | DE Weight Required | Filtration Area |
| W3EC40AC | 4 lb | 20 sq ft |
| W3EC50AC | 5 lb | 25 sq ft |
| W3EC65A | 6 lb | 27 sq ft |
| W3EC75A | 7 lb | 40 sq ft |
