1. Wide Applications: Compatible with Dynamic series I, II RTL/RCF, III RTL/RCF and V inline pool/spa cartridge filter for models RDC-25, RDC-25S, RDC-50, RDC-50S, DSC 75, DSC 100. Also compatible with Predator II mini-cellular media cartridge filters 2. Perfect Compatibility: Compatible with Rainbow High Capacity automatic chlorine/bromine pool and spa feeder models HC-3315, HC-3330, HC-3340. Also compatible with pool and spa leaf trap models 179, 179-HDB, 179-C, 179C HDB 3. Direct Replacement: Used to replace the old or worn pool and spa filter lock ring. Replace Part Number: #R172214. Dimension measures 7.44"(Outer diameter)x 6.02"(Inner diameter)x 1.42"(Height). .
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