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When you know your system or housing model number, this page lists the replacement cartridges we match to it—compare length, diameter, and micron rating before you order.
Brand
3M
Model AP903
3M Aqua-Pure AP903 whole house water filter system
Series: Aqua-Pure
These cartridge numbers are matched to this system model in our reference. Compare length, diameter, and micron rating with the filter you’re removing or your housing specs before ordering.
Best match first
AP917HD-S
3M Aqua-Pure sediment cartridge for AP900-series high-flow systems
Replace about every 6 months
All details for this part (notes, compatible models, buying options when listed)
Other parts that also fit this model
Less common crosses — open each for full part details.
Notes & next steps
Search again if you need a different model or part number.
High-flow AP900-class head; commonly serviced with AP917HD-S + AP910R on dual-stage installs — confirm your sticker.