A reliable replacement cartridge designed to keep your spa water clean, clear, and circulating efficiently. The FC‑3915 / C‑6430 / Watkins 30 filter cartridge delivers dependable performance with durable pleated media that captures dirt, oils, and fine debris. Its strong internal core and precision‑fit end caps ensure long service life and easy installation.

This cartridge is ideal for restoring filtration efficiency in Watkins and HotSpring spa systems, helping maintain balanced water and reduce strain on your pump.