American Plumber WLCS-1000 Under-Sink Water Filter System Reduces chemicals including Trihalomethane, pesticides, and herbicides Reduces lead, mercury, chlorine taste & odor, bad taste & odor, fine sediment, and is NSF/ANSI standard 53 certified to reduce cysts such as cryptosporidium and giardia by mechanical means Filter life monitor - lights and sound tell you when to change filter cartridges Reduces particles as small as 0.5 microns in size by mechanical means