The FC4B21080L from Panasonic Corporation is a MOSFET with Drain Source Resistance 18 to 100 milliohm, Drain Source Breakdown Voltage 12 V, Gate Source Voltage 12 V, Gate Source Threshold Voltage 0.4 to 1.4 V, Gate Charge 7.1 nC. Tags: Chip. More details for FC4B21080L can be seen below.