Unicel 4CH-21 Replacement Filter Cartridge for 19 Square Foot Top Load,White

19 Square Foot top load. Replacement for: Alcove; Pageant Spas; Saratoga Spas 20245-238; Unicel 19 Square Foot top load (Note: Replaces any cartridge that has an MPT fitting or a 1.9-inch id with disposable adapter.); Vita Spas PVT 25N (Note: Remove "pad adapter" from the skimmer before threading Unicel MPT directly into the suction fitting.); Atera Spas (Four Seasons Home Resort Products); Dream Maker Spas (Note: Remove "pad adaptor" (if present) from skimmer before threading MPT directly into suction fitting; 2000 to present with LED lights)