[Filter Compatible Models]Our swimming pool filter type S1 is compatible with for all models including 28403E, 28407E, 28443E, 28453E, 28421E, 28423E and 28413E. [Powerful Filtration Performance]Premium quality dacron fabric collects hair, leaves, dust, sediment, sand, etc; easy to clean and replace.The S1 filter is installed inside the filter pump and captures dirt as it passes through the system. [Warm Tip]It is recommended to change the spa filter regularly to maintain filtration efficiency, and replace them every 2-3 weeks to keep the water clean.Provide a larger filter area, make the filter efficiency higher, toughness, resistance to dilute acid, fine filtration, and strong dirt absorption ability. [Easy To Clean]Our type S1 replacement spa filters feature extra- plastic and quality Dacron paper pleats.our spa filters for are so easy to clean,so you can reuse them again and again.Enjoy clean in your pool. [Powerful Filtration Performance]The powerful thrust of the filter can effectively remove hair, leaves, dust, sediment, sand, impurities, etc. Provide you with clear and clean water, allowing you to easily enjoy .