The PG20N04S4L-18A from Infineon Technologies is a MOSFET with Continous Drain Current 20 A, Drain Source Resistance 15.2 to 26 Mohms, Drain Source Breakdown Voltage 40 V, Gate Source Voltage 16 V, Gate Source Threshold Voltage 1.2 to 2.2 V. Tags: Surface Mount. More details for PG20N04S4L-18A can be seen below.