LTWHOME Replacement Polishing Filter Pads Fit for Marineland C-160 & C-220 Canister Filter Packing include: 12 pcs poly filter pads. Change every 3-4 weeks. Custom designed and manufactured for Marineland C-160 & C-220 Canister Filter.  - Provides efficient water flow with less clogging for long lasting filtration. Provides efficient water flow with less clogging for long lasting filtration. Enhances biological filtration.