The GT-SMD181240012-TR is a surface mount surge arrestor intended to protect electronic circuits from transient overvoltage events. It features a DC firing voltage of 400V with a ±20% tolerance and can handle a maximum impulse current of 1 kA (8/20μS). This device exhibits a low inter-electrode capacitance of 1.0 pF maximum and a high insulation resistance of at least 104 MΩ. Housed in a compact 3.2 x 4.5mm package and rated for an operating temperature range of -65°C to 125°C, it is well-suited for protecting sensitive electronics in space-constrained applications.