The MCR1718-6HR from Digitron Semiconductors is a Silicon Controlled Rectifier with Breakover Voltage 400 V, Breakover Current 1000 A, Gate Trigger Voltage 0.8 to 1.5 V, Gate Trigger Current 10 to 50 mA, Temperature Operating Range -65 to 125 Degree C. Tags: Stud Mount. More details for MCR1718-6HR can be seen below.