Replacement Water FilterPre-filter 5µContact Us to PurchaseFeatures Traps dirt, rust, and other impurities. Shrink wrap, clean and reliable. Specification Model Type Spec. Remark FT-0018 String Wound Filter Cartridge, PP 5µ 10" Note Do not use where the water is microbiologically unsafe or of unknown quality without adequate disinfection before or after the unit. The system is to be supplied only with cold water. The system and installation shall comply with applicable state and local regulations.