... main model include the following: 1) Stud type phase control thyristers or silicon control rectifier (SCR), 5A~500A, 100V~5000V, ... and hermetic glass-metal seal selectable. 2) Disc type phase control thyristor or silicon control rectifier (SCR), 5A ~ 5000A, 100V ~ ... hermetic metal case with ceramic insulator. 3) Rotary type phase control thyristor or silicon control rectifier (SCR), 300A ~ 500A, 600V ~ ...