Stmicroelectronics Tyn412Rg.
SCR THYRISTOR, 8A, 400V, TO-220AB; Peak Repetitive Off-State Voltage, Vdrm:400V; Gate Trigger Current Max, Igt:15mA; Current It av:8A; On State RMS Current IT(rms):12A; Thyristor Case Style:TO-220AB; No. of Pins:3Pins; MSL:-