SuperPro Diffuser O-Ring for Pentair Pump 355331 | O-421-9
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SuperPro Diffuser O-Ring for Pentair Pump 355331, O-421-9

Ask a questionMPN O-421-9
$399
Discontinued
This item has been discontinued
The manufacturer no longer makes this item and we cannot restock it. We can help you find a replacement that fits your equipment.
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Quick overview

  • SuperPro O-421-9 Ordered by the SuperPro part number O-421-9.
  • Pentair 355331 Listed for Pentair pump 355331.
  • Diffuser O-ring The O-ring that seals the diffuser.
  • Single O-ring A small seal that is cheap to replace while the pump is open.
  • Not a Pentair part A SuperPro O-ring, not a Pentair OEM part.
  • Compare the old one Check the old O-ring against the new one before reassembly.
Full description and specifications ↓

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Product details

The SuperPro O-421-9 is a diffuser O-ring listed for Pentair pump 355331.

What it does

The O-ring seals the diffuser. Like any seal in a pump, it is a wear item, and a flattened, cracked or hardened O-ring is worth replacing whenever the pump is opened.

Before you order

This is a SuperPro O-ring, not a Pentair OEM part. Check the Pentair number 355331 against your pump and compare the old O-ring against the new one.

From Pool School

How to Prime a Pool PumpFrom the breaker to a full pot, each manufacturer's time limit, and what to check when it won't catch prime. Read Replace the Pool Pump Motor or the Whole Pump?The manufacturers' tests first, what each repair replaces, and the federal motor rule. Read
Specifications
Brand SuperPro
Manufacturer part number O-421-9
Type Diffuser O-ring
Fits Pentair pump 355331
Pack size Single O-ring
Shipping weight 2 lb
Ships Parcel

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Questions and answers

What people ask about this product, answered by our pool techs.

What does SuperPro O-421-9 fit?
SuperPro O-421-9 is the diffuser O-ring listed for Pentair pump 355331.
Is this a Pentair part?
No. O-421-9 is a SuperPro O-ring, listed for Pentair pump 355331.
Is this one O-ring or a kit?
It is a single diffuser O-ring.
How do I confirm it is the right O-ring?
Check the Pentair part number 355331 against your pump, and compare the old O-ring against the new one before reassembly.
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