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OP-GF1 Replacement Filter Cartridges

A filter with no spare is a countdown. When the cartridge is done, so is your clean water.

Genuine replacement cartridges for the Outlast Family Gravity Filter (OP-GF1). Same hollow-fiber core, same fit. Keep two in the kit so a used-up filter never becomes the emergency.

  • Fits the OP-GF1 only, no adapters
  • Up to 1,400 gallons per cartridge
  • Backflushable, no tools
  • Sealed, no expiration in storage
  • Two spares covers a family for a year
$34.96 $50.00 SAVE 30%

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"Ordered the 5 pack the same day as the filter. Cheap insurance."

Mike R.

Questions?

Frequently Asked Questions

Will these fit other gravity filters?

No. They are built for the Outlast OP-GF1 housing and thread.

How do I know when to replace one?

Flow slows noticeably and does not recover after a backflush. Most families see well over 1,000 gallons first.

How should I store spares?

Dry, in the sealed pack, anywhere above freezing. A cartridge that has never been wet has no shelf life.

Never Let the Filter Be the Weak Link

  • Genuine OP-GF1 fit
  • 1,400 gallons each
  • Sealed for storage
  • Ships free
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