ETZ Aquarium Filter O-Ring Seal Kit, 7-Piece Replacement for FX5/FX6

The ETZ O-Ring Seal Kit replaces worn or damaged seals to restore sealing on compatible FX5 and FX6 aquarium filters, with seven rubber rings across three part types.

• Seven replacement O-rings in three types — match the seals being replaced.
• Compatible with FX5 and FX6 filter units A218 and A219 — choose the kit for these models.
• Includes A-20210, A-20207 and A-20212 seals — covers the top cover, motor and snap-on cover positions.
• Rubber rings resist wear, aging and deformation — made for replacement sealing use.
• Designed to restore the seal and help prevent leaks — supports proper filter operation.

This replacement kit is for maintaining the seals on compatible aquarium filters when an existing O-ring is old or damaged. A worn seal can affect sealing and contribute to leaks; replacing the corresponding ring is intended to restore the seal and support the filter’s proper function. Confirm the filter model before choosing the kit: it is for FX5 and FX6 units, not FX4.

Which filter models fit this ETZ O-Ring Seal Kit?

The kit fits FX5 and FX6 aquarium filter units A218 and A219. It is not suitable for FX4, so compare the model of your filter before selecting it. The replacement rings are identified by their A-number part codes for matching them to the relevant sealing position.

• Compatible filter units: A218 and A219.
• Filter models: FX5 and FX6.
• Not compatible with FX4.

Which replacement seals are included?

The ETZ kit contains one A-20210 top cover seal, two A-20207 motor sealing rings and four A-20212 top snap-on cover O-rings. These quantities provide replacements for the three listed seal types; match each ring to its corresponding position when replacing an old or damaged seal.

• A-20210 top cover sealing ring: 1.
• A-20207 motor sealing rings: 2.
• A-20212 top snap-on cover O-rings: 4.

How do you replace the filter O-rings?

Remove the old or damaged A-20210, A-20207 or A-20212 ring from its corresponding position, then fit the replacement ring of the same type. Replacing the relevant seal is designed to restore sealing, help prevent leaks and support proper operation of the aquarium filter system.

• Identify the seal by its A-number and filter position.
• Remove the old or damaged ring before fitting its replacement.
• Use the matching ring type for the top cover, motor or snap-on cover.

This kit suits aquarium owners maintaining a compatible FX5 or FX6 filter whose existing seals need replacement. Its three identified seal types and specified quantities make it a model-specific option for replacing those rings, rather than a kit for FX4 filters.

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