A polarizable electrode for use in an electrical double layer capacitor, which includes carbon fine-powders, a conductive auxiliary agent, and a binder. Each platform provides a plurality of one-way valves of two sizes. Since the microstrip-type BALUN is realized by a microstrip line which is a distributed constant line, the microstrip-type BALUN has an excellent performance even for high-frequency signals. As the corrosion process proceeds, an accumulation of oxides increases the localized pressure to cause cracking within the concrete. Banded strands dispose on each rod in relation to the collar.