Find your parts diagram
Sticker on the pump body (the part with the basket), not on the motor. Motor labels from Century, A.O. Smith or Regal won't match parts.
Label on the side of the tank near the base. Size is in sq ft, e.g. 420 sq ft = C4030 or CCP420.
Rating plate inside the front access panel. Note the BTU and gas type (NG or LP).
Molded into the body or printed on top. Robotic cleaners: on the power supply.
Still not sure? Call (818) 818-6559 and we'll find it for you.
Pentair 355331 Diffuser O-Ring | SuperFlo & Challenger Pumps
Fits these models (4)
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Goes with this part
CA P65 Warning: Cancer and reproductive harm. www.p65warnings.ca.gov
Other parts on the same Pentair SuperFlo VST Pump
The Pentair Diffuser O-Ring 355331 is a genuine OEM replacement for SuperFlo VS/VST and Challenger pumps made after 6/17/19. Designed to provide a tight seal within the pump diffuser, this O-ring prevents water leakage that can lead to reduced efficiency or damage. Made from durable, pool-grade materials, it resists chlorine and constant water exposure to deliver long-lasting performance. By replacing worn or damaged O-rings with OEM parts, you help extend pump life and maintain consistent system reliability. This component is essential for keeping pumps sealed, efficient, and operating at peak capacity.
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Exact OEM Fit: Pentair 355331 O-ring designed to original factory specifications for SuperFlo VS/VST and Challenger pumps.
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Leak-Free Seal: Creates a watertight connection in the diffuser assembly, protecting the pump from efficiency loss.
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Durable Material Build: Manufactured from chlorine- and chemical-resistant rubber for extended use in pool environments.
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Critical to Maintenance: Regular O-ring replacement prevents leaks and maintains consistent system performance.
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Supports Optimal Efficiency: Helps sustain water pressure and circulation, keeping pumps running smoothly.
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Long-Term Reliability: Genuine OEM construction ensures long service life and dependable function.
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Easy Installation: Designed for quick, direct replacement to restore pump sealing capability.
- (1) Pentair 355331 Diffuser O-Ring
For pumps manufactured after 6/17/19
- Pentair SuperFlo VS / VST Pumps
- Pentair Challenger Pumps
- Pentair Diffuser - 355949
Note: This o-ring may be compatible with your pump, please refer to your systems owners manual to ensure compatibility.
