Sta-Rite / Berkeley / Pentair Diffuser Ring C21-2

Pre-cut diffuser ring gasket (C21-2) for Sta-Rite, Berkeley, and Pentair D-series / ED-series pumps. Sized to seat cleanly on the diffuser, providing uniform compression and a leak-tight seal after service or rebuilds.

Cross-references & use:

• Part: C21-2 Diffuser Ring

• Also called: D-Series Diffuser O-Ring / Gasket

• Pump families: Sta-Rite D & ED series (Berkeley/Pentair equivalents)

Why choose this part:

• Direct-fit profile for fast, reliable installs

• Consistent thickness for even sealing pressure

• Smooth edges for easier alignment during reassembly

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