The 1/4" fnpt fitting is not include with the filter. It is well known as the exterior ice maker & water filter. Compatible with GE GXRTDR, Culligan IC-100A, Omnipure K2533JJ, Samsung DA29-10105J, Whirlpool WHKF-IMTO, WSE-100, IL-IM-01, WIC-6A, R200, DD-7098, EF-9603, K2533JJ, 5231JA2010A, 5231JA2010B, 5231JA2012A, WSI-1, USC100, etc.
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