The BT151-800R from Shenzhen Huake Semiconductor is a Silicon Controlled Rectifier with Breakover Voltage 800 V, Breakover Current 120 A, Gate Trigger Voltage 0.7 to 1.5 V, Gate Trigger Current 4 to 15 mA, Temperature Operating Range -40 to 125 Degree C. Tags: Through Hole. More details for BT151-800R can be seen below.