STMicroelectronics Surface Mount, 3-pin, TRIAC, 800V, Gate Trigger 10V

The STMicroelectronics Overvoltage protected AC switch is a high performance switch can control a load of up to 0.8 A. This device switch includes an overvoltage crowbar structure to absorb the inductive turn off energy, and a gate level shifter driver to separate the digital controller from the main switch. It is triggered with a negative gate current flowing out of the gate pin.

High noise immunity against static dV/dt and IEC 61000 4 4 burst
Needs no external protection snubber or varistor
Enables equipment to meet IEC 61000 4 5 surge
Clamping at VCL then crowbar action