REPLACEMENT MODELS - Replaces Filbur FC-0359 spa filter,PWW50P3, Unicel 6CH-940, and Waterway 817 0050, 03FIL1400, 25252, 378902, and PWW50. POWERFUL FITRATION PERFORMANCE - Innovated inchDirt-Locking inch technology make the fabric traps much more contaminants than regular fabric. This filter efficiently removes hair, leaves, dust, sediment, sand, etc. Enjoy clean leisure time in your spa and hot tub. MORE EFFICIENT FILTRATION AREA -Unicel 6ch-940 spa filter cartridge is made from Dacron material, easy to clean and replace, washable and reusable. The Dacron material fibers also helps catch particles, increases efficiency without the pressure drop penalty, and helps reduce filter cleanining frequency. LONG SERVIVE LIFE - Unique Trilobal Filtration Fabric Structure make it easier to capture large volume of contiminants. It is also easy to wash/clean to recondition the filter. This filter lasts for 1-2 years when proper maintenance is performed. EXCELLENT SERVICE -The package includes 2 pieces unicel 6ch-940 spa filter.Welcome to contact us by visiting our store, if you have any question about our spa filter cartridges just contact us via service email, we offer 7days/24hrs Customer Service. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-Dadangjia