0.5 sub-micron Pb1 Filter Sub-micron cabon filter for cyst removal as well as chlorine, tastes, odors, and chemicals Removes cysts Including Cryptosporidium, Giardia, Entamoeba and Toxoplasma Standard 10" Common size used in RO systems, drinking water filters, and other point-of-use applications Standard Size Industry standard size fits standard 10" filter housings - Approximate dimensions 9-3/4"x 2-1/2" Replacement carbon block filter fits standard 10" filter housings. Typical life expectancy varies greatly depending on water parameters and useage. Recommended replacement is at least once a year, with every six months typical.