The Omnipure K-Series K5686 inline filter has fittings that make this filter easy to install and replace. This filter can be used in ice makers, refrigerators, beverage equipment, drinking fountains, under the counter systems, R.O.Systems and in conjunction with purification systems. This filter aids in the removal of taste, odor and chlorine taste and odor along with a polyphosphate scale inhibitor to reduce lime and scale.

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"

*NOTEA 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.