Pentair Sta-Rite 11" Black Cartridge Filter O-Ring for Posi-Flo II | WC9-3

Pentair Sta-Rite 11" Black Cartridge Filter O-Ring for Posi-Flo II | WC9-3

OEM Pentair Sta-Rite 11" black cartridge filter O-ring for Posi-Flo II PTM series and PTM135 filters. Helps restore a proper tank seal.

Features

• Genuine Pentair Sta-Rite replacement cartridge filter O-ring.
• Fits Posi-Flo II PTM50, PTM70, PTM100, and PTM135 series filters.
• Black O-ring design for tank sealing service.
• Also referenced for separation tank assembly use.
• Direct OEM replacement for worn, leaking, or flattened original O-rings.

Description

The Pentair Sta-Rite WC9-3 cartridge filter O-ring is a model-specific replacement seal for Posi-Flo II cartridge filter systems. It is most consistently tied to PTM50, PTM70, PTM100, and PTM135 filter models. This is not a universal ring. When the original seal is worn out or leaking, replacing it with the correct Pentair Sta-Rite part is the right fix.

Pro Tip

Before reassembly, clean the sealing groove and inspect the tank clamp hardware. A fresh O-ring will not solve sealing problems caused by debris, bad clamp tension, or damaged tank edges.

Installation Tips

Shut the system down fully and relieve all pressure before opening the filter. Confirm the exact Posi-Flo II model before ordering, seat the O-ring evenly, and avoid twisting or pinching it during reassembly.

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• Pentair Warranty
  
• A&A (Pentair In-Floor) Warranty
  
• Fluidra Warranty (Zodiac / Jandy / Polaris / Caretaker)
  
• Paramount Warranty
  
• BlueSquare Warranty
  
• Hayward Warranty
  
• All Other Manufacturer Warranties
  

Note: Warranty coverage, registration, and service terms are provided directly by the manufacturer. Please review the details carefully to ensure proper understanding of coverage and claim procedures.