RECOMMENDED USE: Replacement fridge filters; replace water and air filter every 6 months for best results GENUINE REPLACEMENT PART: Part made specifically to be compatible with Frigidaire refrigerators CERTIFICATIONS: NSF Standard 42 Certified to reduce chlorine, taste, and odor; 53 Certified to reduce health related contaminants such as lead, volatile organic chemicals, and asbestos; 401 Certified to reduce emerging chemical compounds