The OmniPure E5420-P E-Series Filter Cartridge is the equivalent to the Everpure OCS EV961801 replacement cartridge. The E5420P is a 1 micron carbon block with a scale inhibitor.
This filter is used for the reduction of chlorine, taste & odor, and scale.
The E5420-P is an Everpure compatible replacement cartridge for Everpure system EV927560. It will not work, however, with the Everpure QL1 Filter Head.