The FTK3903Z from First Silicon is a MOSFET with Continous Drain Current -32 to -50 A, Drain Source Resistance 7.1 to 14 milli-ohm, Drain Source Breakdown Voltage -30 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage -1.2 to -2.5 V. Tags: Surface Mount. More details for FTK3903Z can be seen below.