This document describes test procedures for measuring the performance of full-flow lubrication oil filters for internal combustion engines according to ISO 4548 standards. It outlines Test A which evaluates the basic anti-drain performance of inlet and outlet valves, and Test B which tests basic performance plus additional procedures to ascertain supplementary performance. The document references ISO 4548-9 and that FECWorld provides ISO 9001 certified testing equipment for spin-on oil filter anti-drain tests.