This Notice of Warning constitutes formal notification by the United States Environmental Protection Agency, Region 9 (EPA) pursuant to Section 14(a)(4) of FIFRA, 7 U.S.C. Section 136l(a)(4). Based on a review of an import of several unique water filter products, making pesticide claims, to the Airport of San Francisco, California (Port Code 2801), on April 9, 2025, EPA has determined that Katadyn North America, Inc. (KNA), Importer of Record (IOR), violated Section 12(a)(1)(F) of FIFRA, 7 U.S.C. Section 136j(a)(1)(F) with each shipment by distributing a misbranded pesticide devices.