Reverse Osmosis Revolution SR101 10"x2.5" Cation Resin Softener Water Filter for External Dishwasher Softener and RO Systems, Qty of 2 Water Softening Resin Cartridge for External Dishwasher Softener Reduce/Remove: Hardness, Calcium, Magnesium, Iron, Manganese etc. Fit standard 10"x2.5" housing