The STF12N120K5 from STMicroelectronics is a MOSFET with Continous Drain Current 12 A, Drain Source Resistance 620 to 690 Milliohm, Drain Source Breakdown Voltage 1200 V, Gate Source Voltage -30 to 30 V, Gate Source Threshold Voltage 3 to 5 V. Tags: Through Hole. More details for STF12N120K5 can be seen below.