Overview Bring your Jacuzzi spa back to spa-day perfection with the Poolzilla replacement filter cartridge designed for Jacuzzi Premium J-300 and J-400 series hot tubs. This generously sized cartridge measures 15.5 inches in length and 6.625 inches in outer diameter, with finely pleated polyester media that captures the body oils, lotions, sunscreen, and microscopic debris that turn clear spa water cloudy. The accordion-style pleats create a huge dirt-trapping surface area, meaning your filter pulls more gunk out of the water with each cycle and goes longer between cleanings. Sturdy molded end caps form a leak-proof seal inside your filter canister, so every drop of water passes through the media — not around it — for the silky-clear water your spa was built to deliver. Spa filters work harder than pool filters because the water volume is smaller and the bather load is bigger, so plan to rinse this cartridge every two to four weeks and replace it every 12 to 15 months — or sooner if you notice water staying cloudy after shocking, or your jets feeling weaker than usual. A fresh filter takes the strain off your pump, helps your sanitizer work more efficiently, and keeps the water genuinely clean for the people you love. Swapping it out takes just a couple of minutes: power down the spa, lift out the old cartridge, drop the new Poolzilla filter in, and you're back to soaking. Order one now — and grab a spare while you're at it — so your spa is always ready when you are. What's Included Your order includes the selected quantity of replacement spa filter cartridges. Each unit is individually inspected for quality before shipping.