T540 & T541 HRA Capacitors KEMET T540 and T541 Series, part of KEMET's Organic Capacitor (KO-CAP) product class, are comprised of first-to-market polymer cathode technology High-Reliability Series (HRA) capacitors for military and aerospace applications. The T540 series and the T541 series from KEMET have several key features, including high-frequency capacitance retention, benign failure mode, volumetric efficiency, and low ESR values.