Reduce your use of chlorine water treatments with the Eco Pur Mineral Filter (Old Style - 2002 to 2003). This mineral spa filter from Eco Pur is a closed-top style and features a molded handle and a male threaded bottom fitting. This product fits inside the Micro Outer Filter. The Eco Pur Mineral Filter (SKU: X268057) for older Down East Spas and the Legend Series by Master Spas® features a unique mineral composition that neutralizes acids and kills bacteria without throwing off the pH level in the your hot tub or spa.