The IXFA50N20X3 from Littelfuse is a MOSFET with Continous Drain Current 50 A, Drain Source Resistance 30 Milliohm, Drain Source Breakdown Voltage 200 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 2.5 to 4.5 V. Tags: Surface Mount. More details for IXFA50N20X3 can be seen below.