PA100N / C-7487 / FC-1270
100 sq ft replacement filter cartridge • 7″ OD × 25.5″ long
The PA100N is the tall single cartridge for Hayward's Super-Star-Clear C4000 series (C4000, C4000S, C4020). It's 100 square feet in a 7-inch-wide element that stands 25-1/2 inches tall. Hayward's number is CX870-XRE, also written CX870RE, and the cross-references are Unicel C-7487 and Filbur FC-1270. One point of confusion is worth clearing up: the four-cartridge Hayward SwimClear filters use a similar-looking element, the PA106, at the same 25-1/2-inch height. But that's a set of four, and this is a single. Read your tank's model number. Super-Star-Clear takes one of these; SwimClear takes four of the other.
Compare on Amazon
PA100N replacements on Amazon
The buttons below pull up Amazon results for each cross-reference part number. Same physical cartridge, different stickers, often different prices. Cross-shop and pick the cheapest option that has solid recent reviews.
Cross-Reference & Interchangeable Part Numbers
| Brand | Part Number | Type |
|---|---|---|
| Pleatco | PA100N | Primary |
| Unicel | C-7487 | Equivalent |
| Filbur | FC-1270 | Equivalent |
| OEM | Hayward CX870-XRE | Original Equipment |
| OEM | Hayward CX870RE | Original Equipment |
Always verify dimensions and end-cap type before purchasing a replacement.
Compatible Pool Filter Systems
| Brand | Model |
|---|---|
| Hayward | Super-Star-Clear C4000 |
| Hayward | Super-Star-Clear C4020 |
Frequently Asked Questions
What are the dimensions of the PA100N?
The PA100N is 7 inches in outer diameter, 25.5 inches long, with an open top and an open bottom. Total filtration area is 100 square feet. Before ordering, pull your existing cartridge and measure it yourself, or check the label inside the housing. OD and length both have to match within about an eighth of an inch, and the end-cap style needs to match exactly so the cartridge seats properly when the lid closes.
What other part numbers are interchangeable with the PA100N?
PA100N is the same physical cartridge as C-7487, FC-1270, plus OEM versions like Hayward CX870-XRE, Hayward CX870RE. Same dimensions (7" × 25.5"), same open top, same open bottom. The Pleatco, Unicel, and Filbur boxes ship the same media inside, just with different stickers. The only thing to watch is the end-cap style: if a cross-reference has a slightly different cap design, it may not seat right in your housing.
Is the Hayward CX870-XRE the same filter as the PA100N?
Yes. Hayward CX870-XRE is an OEM number, the code the tub or pool builder stamps on the cartridge they ship. The filter itself is made by Pleatco, Unicel, or Filbur, so Hayward CX870-XRE (along with Hayward CX870RE) and PA100N, C-7487, FC-1270 all point to one interchangeable cartridge. Buy whichever is cheapest with solid recent reviews, and just check that the dimensions match your old cartridge before you order.
How often should I replace the PA100N?
The PA100N holds 100 sq ft of media, so it has a healthy buffer before it clogs for good. Plan on 18 to 24 months in a normal residential pool. The pressure gauge is the honest signal here: an 8 to 10 psi rise over the clean pressure that a soak can't reverse means it's time. Channeling, tears, or fibers that won't rinse clean are the other reasons to swap it early.
How do I clean the PA100N?
The PA100N has open ends on both top and bottom, so water flows straight through. Pull the cartridge from the housing and hose it down. Hit the pleats from above at about a 45-degree angle so water rinses debris out instead of packing it deeper, and work top to bottom while rotating the cartridge. Skip the pressure washer. The high pressure tears or collapses pleats, and once that happens you've lost media that doesn't come back. Every few months, give it a deeper clean: soak in a dedicated pool filter cleaner per the product's dwell time, then rinse it down completely before reinstalling. Keeping a spare cartridge on the shelf is genuinely worth it. You swap, run the soak overnight, and the pool keeps filtering.
Which hot tubs and spas use the PA100N?
Pull your existing cartridge and read the part number off the end cap, or check the label inside the filter compartment. That's the most reliable way to confirm compatibility.
Dimensions
Specifications
| Outer Diameter | 7″ |
|---|---|
| Length | 25.5″ |
| Top Type | Open (no end cap) |
| Bottom Type | Open (no end cap) |
| Filtration Area | 100 sq ft |
| Primary Brand | Pleatco |
| Part Number | PA100N |
Fitment notes
3-inch top and bottom openings. Hayward Super-Star-Clear C4000, C4000S, C4020. Also SwimClear C4020 (older).