The Omnipure K-Series K2328 filters feature 1/4" and 3/8" Quick-Connect fittings that make this filter really easy to install and replace. It can be used in refrigerators, ice makers, any reverse osmosis system and many under-counter water filtration systems. It also helps remove chlorine taste and odor, and taste and odor in the water. Dimensions: 2" W X 6" L Flow Rate: .5 GPM Maximum Pressure: 125 PSIG Maximum Temperature: 100 F Service Life: 1 Year or 1000 Gallons Filtration Media: Granulated Activated Carbon Volume Cubic Inch: 9.5 Reduces: Chlorine Taste Odor Fitting Size: Quick-Connect 1/4" and 3/8" fittings Omnipure K2340 has been tested for performance under NSF Standard 42. **Interchangeable carbon with T28, T33 and T40 models. National Pipe Thread (NPT) Size Measured Against a Ruler* Actual Diameter (Inches) National Pipe Thread (NPT) (Fractional) 0.405" 1/8" 0.540" 1/4" 0.675" 3/8" 0.840" 1/2" *NOTE: A very common misconception is that a 1/4" NPT measures as 1/4 inch on a ruler or tape measurer. However, that is not the case. NPT will measure larger in diameter. Above is a sizing reference to help clarify.