Culligan D40 Level-4 Drinking Water Replacement Cartridge
The Culligan D-40-D Level 4 Carbon Block Water Filter reduces Giardia, Cryptosporidium cysts, Lindane, Atrazine (a pesticide and herbicide), asbestos, and mercury.  It will also reduce chlorine taste, odor, and sediment. The filter comes with a 0.5-micron (nominal) filtration and has a filter life of 6 months or 600 gallons.