The FTK4003N from First Silicon is a MOSFET with Continous Drain Current 0.4 to 0.5 A, Drain Source Resistance 1 to 2 ohm, Drain Source Breakdown Voltage 30 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 0.8 to 1.6 V. Tags: Surface Mount. More details for FTK4003N can be seen below.