The QS6K21FRA from ROHM Semiconductor is a MOSFET with Continous Drain Current -1 to 1 A, Drain Source Resistance 300 to 585 milliohm, Drain Source Breakdown Voltage 45 V, Gate Source Voltage -12 to 12 V, Gate Source Threshold Voltage 0.5 to 1.5 V. Tags: Surface Mount. More details for QS6K21FRA can be seen below.