The STL42P4LLF6 from STMicroelectronics is a MOSFET with Continous Drain Current 42 A, Drain Source Resistance 15.5 to 26 Milliohm, Drain Source Breakdown Voltage 40 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 1 to 2.5 V. Tags: Surface Mount. More details for STL42P4LLF6 can be seen below.