Omnipure OMB-934-1ML Chloramine cartridge This cartridge is a 1 micron absolute so it is 0.4 nominal chloramine, rated for heavy metals and cysts, the Omnipure OMB-934-1ML-chloramine catalitic extruded activated carbon cartridge to remove the chloramine. Rated for treatment of Giardia and cryptosporidium cysts as well as lead and other heavy metals treatment.