The FK9B0439ZL from Nuvoton Technology is a MOSFET with Continous Drain Current 7.1 to 13.8 A, Drain Source Resistance 9.5 to 18 milli-ohm, Drain Source Breakdown Voltage 40 V, Gate Source Voltage -10 to 12 V, Gate Source Threshold Voltage 1.0 to 3.0 V. Tags: Chip. More details for FK9B0439ZL can be seen below.