Purify water before fill pool or spa with the new Micro-Klean fill cartridges. Available in disposable version this filter reduce total dissolved solids (TDS) from water and increase the quality of pool or spa water. Attach the Micro-Klean filter to the end of any garden hose and begin the fill. Top hose fitting, closed bottom. Measures 2-3/4-inch outside diameter by 10-inch length.