The KP1800A from HUAJING RECTIFIER is a Silicon Controlled Rectifier with Breakover Voltage 100 to 6500 V, Breakover Current 22500 A, Gate Trigger Voltage 0.8 to 3.0 V, Gate Trigger Current 40 to 300 mA, Temperature Operating Range -40 to 125 Degree C. Tags: Disc. More details for KP1800A can be seen below.