The 2N1872AHR from Digitron Semiconductors is a Silicon Controlled Rectifier with Breakover Voltage 100 V, Breakover Current 15 A, Gate Trigger Voltage 0.4 to 0.8 V, Gate Trigger Current 30 to 200 µA, Temperature Operating Range -65 to 150 Degree C. Tags: Through Hole. More details for 2N1872AHR can be seen below.