The Omnipure K-Series (K2305) Filter is a 5 micron sediment filter built to remove dirt, sand, and sediment. The fittings come in 1/4" and 3/8" John Guest Quick Connect options that make this filter really easy to install. Dimensions: 2" W X 6" L Flow Rate: .5 GPM Maximum Pressure: 125 PSI Maximum Temperature: 100 F Rating: 5 Micron Rating Features: Polypropylene depth filtration Fitting Size: 1/4" OD Quick Connect, and 3/8" OD Quick Connect 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.