The FC4B21210L from Panasonic Corporation is a MOSFET with Drain Source Resistance 8 to 31.5 milliohm, Drain Source Breakdown Voltage 12 V, Gate Source Voltage 8 V, Gate Source Threshold Voltage 0.35 to 1.4 V, Gate Charge 9.4 nC. Tags: Chip. More details for FC4B21210L can be seen below.