This Pentek S1-20BB pleated cellulose filter cartridge reduces sand, dirt, silt, rust, and scale particles in residential and commercial water. It has a nominal filtration rating of 20 microns at an efficiency of 85%. The filter is made of cellulose media pleated around a polypropylene core for strength. It has an initial pressure drop of 1.2 pounds per square inch (psi) at a flow rate of 10 gallons per minute (gpm), and operates over a temperature range of 40 to 145 degrees F (4.4 to 62.8 degrees C). This pleated filter cartridge is for use in various applications, including drinking water purification, irrigation, and industrial processes, among others.