The Vortex Replacement Carbon Post Filter is an Omnipure K2540KK replacement filter for Vortex Water Distiller Kits. This carbon post filter is made with coconut shell carbon and is designed to help reduce chlorine, taste, and odor from water after distillation. It is tested and certified by NSF to Standard 42. Made in the U.S.A. Product Details Replacement carbon post filter for Vortex Water Distiller Kits Omnipure K2540KK replacement filter Made with coconut shell carbon Granular Activated Carbon, also known as GAC Helps reduce chlorine, taste, and odor Does not remove healthful, naturally occurring minerals Tested and certified by NSF to Standard 42 1500 gallon capacity Made in the U.S.A. Replacement Schedule Replace every 6 months to 1 year due to bacterial growth.