The STP55NF06FP from STMicroelectronics is a MOSFET with Continous Drain Current 50 A, Drain Source Resistance 15 to 18 Milliohm, Drain Source Breakdown Voltage 60 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 2 to 4 V. Tags: Through Hole. More details for STP55NF06FP can be seen below.