The WL+AST kit consists of a working light with automatic start/stop device to be mounted in the hood of an extraction arm. The WL is a clear halogen lamp that can be switched on/off by a tumbler switch on the hood of the extraction arm.
The AST is an optical sensor that reacts to the infrared light of the welding arc. Consequently, the connected extraction system is switched on automatically when the welding starts and stops when the welding has finished.