100/150/200 MICRON 4" INCH RING, 15" LONG FELT FILTER SOCK AQUARIUM MARINE SUMP

100 micron is finer however will need cleaning more often than a 150 or 200 micron bag. 1 x AQUARIUM POLYESTER FELT FILTER SOCK. ● Made from high quality durable polyester felt material on a plastic ring with handle, all aquarium safe materials.

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