The RCJ451N20 from ROHM Semiconductor is a MOSFET with Continous Drain Current -45 to 45 A, Drain Source Resistance 42 to 125 milliohm, Drain Source Breakdown Voltage 200 V, Gate Source Voltage -30 to 30 V, Gate Source Threshold Voltage 3 to 5 V. Tags: Surface Mount. More details for RCJ451N20 can be seen below.