The TF809-1200-20 from Greegoo Electric is a Silicon Controlled Rectifier with Breakover Voltage 2000 V, Breakover Current 15000 A, Gate Trigger Voltage 0.8 to 3 V, Gate Trigger Current 40 to 180 mA, Temperature Operating Range -40 to 125 Degree C. Tags: Disc. More details for TF809-1200-20 can be seen below.