The STH320N4F6-6 from STMicroelectronics is a MOSFET with Continous Drain Current 200 A, Drain Source Resistance 1.1 to 1.3 Milliohm, Drain Source Breakdown Voltage 40 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 2 to 4 V. Tags: Surface Mount. More details for STH320N4F6-6 can be seen below.