Small contractors are compact, all-purpose usable and cost-efficient devices. Therefore they are commonly used in mobile devices for craftsman, do-it-yourselfers and industrial machines. These machines are often moved between workspaces. These movings or placing materials on the devices can result into shakings. With the feeder plugged in that can cause an accidental tripping of the machine. The reason are the heavy armatures of these contactors which may trigger when beeing shocked. To avoid this a patented attachment was developed which avoids this accidental tripping of the machine.