Darlly SC863 (or 50327) 193mm 152mm Handle 1.5" SAE Coarse. InSpire SS04 Filter. Unlike the "open hole" filters found in trade-grade spas, the SS04 features amoulded handle and abuilt-in threaded base, ensuring a secure, pressurized seal that prevents "bypass" (unfiltered water leaking around the edges).
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