Check the listing for details. Strong Type Cation For Hardness Reduction Softening w Refillable Housing - 5 Lbs. Condition: New. Listed at 56.95 USD. Strong Type Cation / 5 Lbs Bulk Resin with Empty Refillable Filter Housing Size 2.5 inch x 9.75 inch A High Capacity Cation Exchange Resin for Domestic Applications (Hardness Reduction & Water Softening) Five pounds of cation resin is enough to refill a 2-inch x 10-inch in-line refillable filter housing about 10 times or 2.5 inch x 10-inch refillable filter (for standard 10" housing) about 7 times. Our high-grade cation softening resin is ideal for applications where the reduction of TDS or hardness is required or can be used as a pre-filter to prevent the build-up of scale on sensitive equipment. Specifications: Maximum Recommended Flow: 1.0 GPM ( 3.79 LPM)Each filter estimated capacity is 1040 grains or 17,800 PPM Estimated Capacity: Total 5600 Grains / or Approx 96000 PPM Operation Temperature 40°F to 100°F (Maximum Temperature) Maximum Pressure: 125 PSI 5 micron nominal filter rating Total Weight: 5 lbs Filter Media: Cation Resin Filter Life: Approximately 10500 Gallons Cation Exchange Resin Cartridge for Hardness Reduction, Softening your water by releasing Hydrogen (H+) ions or other positively charged ions in exchange for impurity cations present in the water. The process involves passing water containing hardness ions, namely calcium (Ca2+) and magnesium (Mg2+) through a column containing a strongly acidic cation exchange resin in the sodium (Na+) form (i.e. the exchangeable cations are sodium). The calcium and magnesium ions are exchanged for an equivalent number of sodium ions. The resin, once exhausted, (i.e. all the available sodium ions have been exchanged) must be re-charged. This entails passing a solution containing a high concentration of sodium salts such as brine (sodium chloride) through the ion exchange resin - a process known as regeneration. Commons Cations: Hydrogen (H+), Sodium (NA+), Potassium (K+), Calcium (CA+2), Magnesium (MG+2), Ferrose (FE+2), Ferric (FE+3)