ALKAMEDI ionizers are using a single filtration system with 3 different filter types at the moment offers the most reliable and powerful water filter with state-of-art technology of ALKAMEDI. â? � � � � FB2 : 6 steps of Carbon Block Compound Filter â?¡� � � � FU3 : 8 steps of Advanced Ultra Hollow Membrane Purification Filter â?¢� � � � FNC : 7 steps of NANO Silver Carbon Block Compound Filter The effectiveness of the filtration is determined by the valid filtration capacity verified by a testing institution, and this product is composed of a nano-carbon block composite with a valid water capacity of 3,600 liters for approximately 6 months. It is recommended to use for approximately 6 months and a voice guide will inform you when it is time to replace the filter. Alkamedi does have all kinds of certificates related to each continents and countries we export to such as  CE, CB, UL, NRTL, TUV� etcâ?¦in order to meet all electrical regulations in each countries and regions.