The JSM3420S from JSMicro Semiconductor is a MOSFET with Continous Drain Current 3.6 to 6.0 A, Drain Source Resistance 19 to 63 milli-ohm, Drain Source Breakdown Voltage 20 V, Gate Source Voltage -10 to 10 V, Gate Source Threshold Voltage 0.4 to 1.1 V. Tags: Surface Mount. More details for JSM3420S can be seen below.