Feature: 1. Strong Compatibility: Change your filter to get purer water in your pool or spa with these alternative cartridges compatible with PLEATCO PWW50L, for UNICE 4CH 949 and for Filbur FC 0172. 2. Extend Filter Life & Self-Relaxation: Can help extend filter life and protect your pool or spa. Provide safe and purified water to provide the best leisure experience. 3. Convenient to Clean: Filter products are designed to be durable and easy to clean, so you can keep your pool and spa clean and safe for you and your family. 4. Replace Once a Week: For maximum effectiveness, clean cartridges once a week and change them monthly or sooner. Maintain the filter performance to provide you with clean water. 5. Good Performance: Despite professional manufacturing and superb craftsmanship, the swimming pool filter provides optimal and stable performance. Specification: Item Type: Spa Filter Product Material: Polyester Mesh Weight: Approx. 700g / 24.70oz Product size: about 378 x 125mm / 12.88 x 4.92in Application: For hot tub, spa, children's pool, etc. Note: The data are all measured manually, please allow 1-3cm error due to differences in light and display, there may be some color differences, please refer to the actual item received. Note: The data are all measured manually, please allow 1-3cm error due to differences in light and display, there may be some color differences, please refer to the actual item received.