A full flow filter designed to be installed in the upper radiator hose of your automobile. It prevents rust scale, rubber, gasket material and other matter from clogging your radiator. Available in clear plastic, aluminum, and brass, Comes in 3 sizes, small, medium and large. The filter screen is 15 mesh with 225 openings per square inch. Kit includes 2 clamps. Small measures 1-1/8" to 1-3/8"