The CAP ALUM POLY 220UF 20 6.3V SMD is a type of electrolytic capacitor made from aluminum and polymer materials. It has a radial design with a can-type package and surface mount designations, measuring 220 microfarads at 6.3 volts. The specifications also mention a resistance value of 15 milliohms and an operating temperature up to 105°C, with a lifespan of 2000 hours.