Yer basic, decent quality, made-in-Taiwan temperature controller. You need a temperature controller for your soldering iron so you don't overheat it and cause the tip to become permanently fused in place, which basically ruins your iron. Also, a temperature controller allows you keep the tip just hot enough to melt the solder but not so hot that it causes the flux to spatter and blacken. Solid state, 250 watts, 120 VAC.