[Size]: Massage bathtub filter element replacement, Opening: 150mm; Length: 210mm; Coarse Thread: 38mm. Please measure your return water filter before ordering and compare it with the size of this filter [Applicable Model]: Replaces Pleatco PWW50-P3, PWW50P3, Unicel 6CH-940, Filbur FC 0359, Waterway Plastics 817- 0050, 03FIL1400, 25252, 378902 [Sturdy and Durable] The whole filter adopts an unbreakable handle, a high-fluidity ABS inner core and a thick filter cloth to form a sturdy and durable body, which features high strength and high temperature corrosion resistance. [Foldable Design]: More folds of the filter element mean improved filtering capacity. The three-layer laminated polyethylene inner mesh is covered with a weatherproof and tear-resistant top layer that ensures that the folds remain clear, well-defined and evenly distributed. [Long service life]: The unique structure of the filter cloth makes it easier to catch and remove stains. Therefore, you can easily clean the