The VS-50RIA100 from Vishay is a Silicon Controlled Rectifier with Breakover Voltage 1000 V, Breakover Current 1200 to 1490 A, Gate Trigger Voltage 2.5 to 3.5 V, Gate Trigger Current 50 to 250 mA, Temperature Operating Range -40 to 125 Degree C. Tags: Stud Mount. More details for VS-50RIA100 can be seen below.