This filter cartridge is made of stainless steel fiber sintered felt via a pleating process. The sintered felt can be produced in multi-layer gradient structures from coarse to fine, featuring high porosity, large dirt holding capacity, excellent filtration accuracy, high temperature resistance (up to 650 °C), corrosion resistance, and high mechanical strength, while easily fabricated into different shapes and sizes. The pleated design increases filtration area significantly and allows for cleaning and reuse to lower operational costs. In the pharmaceutical industry, it is widely used for high-precision air and water purification, and is also applicable in petrochemical, chemical medium separation where stringent filtration is required. Common materials include SUS316L and Fe-Cr-Al fibers, providing excellent stability and durability.