Hydrotools by Swimline Cartridge Filter Replacement Elements offer the highest level of pool filtration resulting in crystal clear, clean pools. All Hydrotools cartridge elements are designed with newly innovated, extra dense filtration material technology that efficiently catches and equally distributes captured dirt. This state of the art filtering technique consistently catches the smallest of debris while relieving stress on your filter pump. The filter's new and improved pleat material make the element incredibly quick and easy to remove, rinse off, and reuse again for optimal performance. The filter is built with chlorine resistant, extra reinforced materials that are designed to work seamlessly under high pressure. Hydrotools is an independent brand that specializes in filtration technology. If using with other brands, please review replacement element dimensions carefully to determine correct fit.