This First Need Deluxe water filter replacement cartridge has a 0.1 micron carbon matrix filter element which cranks out a rapid 1.8 liters per minute. The First Need by General Ecology has the finest filter among the water purifiers we sell and it also offers the fastest pump rate. One customer tested his out on a pot of coffee and found he had a cup of fresh water on the other end we recommend using the clearest water possible but its a good story. The First Need Deluxe Water Purifier Cartridge has a capacity of 135 gallons which is substantial if you consider that the average person consumes about a half gallon per day. Backpackers like the First Need Purifiers compact size and 15 oz weight complete water filter. The Deluxe Water Purifier now has a redesigned handle which fits comfortably in the palm of your hand.