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Compatible Replacement for Waterco 701038. Cross-References Unicel C-9444.
SKU XLS-938 1PACK · UPC 810625020648
Confirm your fit
The XLS-938 is a replacement cartridge for the Waterco Opal XL180 and Waterco Opal XL270 long 180 sq ft element (paired with XLS-937). It replaces Waterco 701038, along with aftermarket Unicel C-9444.
Each cartridge is 10 3/10" in diameter and 17 1/4" long with a 3" open end cap top and bottom, and carries 184 sq ft of filter media.
We make every cartridge in Austin, Texas, and shipping is free.
Measure your old cartridge cap to cap, then across the widest pleat.
How to measure a cartridge →Measuring your old cartridge
A variance of ⅛" is normal. Anything larger usually means a different housing model — check the number printed on your old cartridge against the compatible parts list before ordering.
Match your filter housing below, click any part number to verify the fit, or paste your existing part number into the search box.
Filter housings and systems this cartridge fits
OEM and competitor cartridge part numbers this product replaces
The Perfect Fit Guarantee applies to the cross-references listed here. Brand names, models and part numbers identify compatibility only. If your housing is not listed, reach out to our team before ordering.
Can't find your part number? Look it up on the full pool filter cartridge cross-reference chart.
Still unsure after reading these? Send us the number stamped on your old cartridge and we will confirm the fit.
The Excel Filters XLS-938 replaces Waterco 701038. Aftermarket equivalents: Unicel C-9444.
It fits the Waterco Opal XL180 and Waterco Opal XL270 long 180 sq ft element (paired with XLS-937). If your housing is not listed, match the part number stamped on your current cartridge on our cross-reference chart.
10 3/10" diameter, 17 1/4" long, 184 ft² of media (end caps — top: 3" Open End, bottom: 3" Open End). Matching measurements alone do not prove a fit: some of our cartridges share a size and differ in filtration area or end caps, so check the part number on your old cartridge too.
No. The XLS-938 is an independently manufactured replacement cartridge, made in the USA by Excel Filters and built to match the Waterco 701038 specification. Waterco is a trademark of its owner, used only to show compatibility.
Most pool and spa cartridges last 1–2 seasons with regular rinsing. Replace it when cleaning no longer restores flow, the pleats fray, or the end caps crack.
XLS-939 • 1-Pack
Low stockReplaces: Waterco 701040
XLS-937 • 1-Pack
In stockReplaces: Waterco 701041, Unicel C-9443
*Perfect Fit Guarantee applies to the OEM and aftermarket cross-references listed on this page; brand names, models and part numbers identify compatibility only. We ship to the 48 contiguous United States only; free standard shipping applies to those orders with no order minimum, and expedited service is priced at checkout. Every cartridge carries a 6-month limited warranty against defects in materials and manufacturing, separate from our 30-day return policy.
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