Original equipment Master Spas Outer Filter for Twilight Series (except TS120 & TS240), and all MP Legend Series Spas, dating from 2009 (Twilight) or 2014 (ML Legend) to current. This filter is used in conjunction with the Eco Pur mineral cartridge PMA-EP2 (part number X268511) and has "PMA25" embossed on the top. New production comes