POOLPURE 6CH-940 Spa Filter 2-Pack Replaces PWW50P3 Unicel 6CH-940 FC-0359 NIB NIB- 2-Pack of POOLPURE 6CH-940 Premium Replacement Spa and Hot Tub Filters. Broad Compatibility: Directly swaps with popular configurations like the Pleatco PWW50P3, Unicel 6CH-940, Filbur FC-0359, and Waterway Front Access Skimmer lines. These high-performance filters are engineered to keep your spa water crystal clear, clean, and safe throughout the season. Advanced Trilobal Fabric: Features point-bonded filtration media that provides up to 40% greater effective surface area than budget alternatives, maximizing water flow and system efficiency. Dirt-Locking Technology: Efficiently captures fine debris including sediment, sand, hair, and leaves. Durable Build Quality: Reinforced structural end-caps offer maximum resistance against chlorine degradation and high chemical environments.