The IXTN550N055T2 from Littelfuse is a MOSFET with Continous Drain Current 550 A, Drain Source Resistance 1.3 Milliohm, Drain Source Breakdown Voltage 55 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 2 to 4 V. Tags: Chassis Mount. More details for IXTN550N055T2 can be seen below.