Leveluk SD 501, DX, DX II, SD 501U, Super 501, Jr. & SUN US. Note: This is the HG-N model for most Enagic Kangen machines sold after 2011. Specifically designed to fit Enagic water ionizers. There are two different filter types for all Enagic machines, the 'original' HG, and HG-N type which has a different shaped center nipple base.
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