The MCR18EZPF4321 part from ROHM is a Schottky Barrier Diode with a maximum forward current of 18A and a maximum reverse voltage of 43V. It has a low forward voltage of around 0.2V, an ultra-low reverse leakage, and a small package size of 4.6 x 8.6mm. It is suitable for various power supply circuit components, such as DC-DC converters, photovoltaic applications, and automotive systems.