Omnipure Filter Company offers three series of replacement filter elements for use in systems or as stand-alone units - the OC-Series, the CS-Series and the OMB-Series. The Slim Line includes all of the engineering features available on the OC-Series in a small, slender profile. With the highest volume in the industry, the OC-Series filter elements are designed to fit most standard 4-7/8", 9-3/4" and 20" cartridge housings. Omnipure utilizes a spring loading device to compress the media, reducing more media migration and ensuring that the water passes properly through the media for optimum filtration. Ask your Omnipure representative about custom formulations and alternative finishing options. less