The MCR72-8TG from Littelfuse is a Silicon Controlled Rectifier with Breakover Voltage 600 V, Breakover Current 8 A, Gate Trigger Voltage 1.5 V, Gate Trigger Current 0.0002 A, Temperature Operating Range -40 to 110 Degree C. Tags: Through Hole. More details for MCR72-8TG can be seen below.