The TK9A55DA from Toshiba is a MOSFET with Continous Drain Current 8.5 A, Drain Source Resistance 680 to 860 Milliohm, Drain Source Breakdown Voltage 550 V, Gate Source Voltage -30 to 30 V, Gate Source Threshold Voltage 2 to 4 V. Tags: Through Hole. More details for TK9A55DA can be seen below.