The DF2S20CT from Toshiba is a Power Diode with Dynamic Resistance 55 ohm, Reverse Current 0.5 uA, Reverse Voltage 18.8 to 21.2 V, Temperature operating range -55 to 125 Degree C, Reverse Breakdown Voltage 18.8 to 21.2 V. Tags: Surface Mount. More details for DF2S20CT can be seen below.