The IRFZ20 from Vishay is a MOSFET with Continous Drain Current 15 A, Drain Source Resistance 100 milliohm, Drain Source Breakdown Voltage 50 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 2 to 4 V. Tags: Through Hole. More details for IRFZ20 can be seen below.