The RF4L055GN from ROHM Semiconductor is a MOSFET with Continous Drain Current -5.5 to 5.5 A, Drain Source Resistance 31 to 66 Milliohm, Drain Source Breakdown Voltage 60 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 1.3 to 2.7 V. Tags: Surface Mount. More details for RF4L055GN can be seen below.