Cartridges are produced with genuine Reemay filter media and durable polyurethane end caps. Prevents harmful bacteria from growing on the cartridge. Less bacteria results in a reduction of foul odors, algae, black mold and other harmful contaminants which foul a cartridge. Antimicrobial protection lasts as long as the cartridge itself. Easier to clean than any other filter. 100 percent polyester core for strength and durability. Polyester Microban sheath for ease of maintenance. Extruded and reinforced PVC center cores. Embossed part numbers. Break-resistant bands. No pad adapters needed. Fits Haven spas, Phoenix spas, Sunbelt spas, Superior spas, Custom molded products, Waterway plastics filter models 25253, 25254, 817-0011. Measures 6-inch diameter by 8-1/4-inch length. Closed top hole, 1-3/4-inch bottom hole. Top crescent handle style, 1-3/4-inch male slip style. 40-Square feet area and weighs 3-ounce. Replaces Unicel, Pleatco, Aladdin filter cartridge models 6CH-941, PWW100ST-P3, 14018.