This filter can only be used in AquaTru Classic and Connect countertop purifiers and the Under the Sink purifier. The Pre/Carbon filter is certified to NSF Standards will last six months or 600 gallons, whichever comes first. The Pre/Carbon Filter reduces sand, silt, sediment, rust and particles from water. Activated carbon reduces chlorine taste and odors and conditions the water before it is treated by the reverse osmosis membrane. Operating Parameters Temperature: Min 4°C. (39°F); Max 38° (100°F)