Abstract: An improved hand-held flat conductor applying apparatus for applying to the receiving surface of a glass pane such as the rear window in a motor vehicle, a plurality of equidistant essentially straight lengths of pre-glued flat conductor for defining the heating lines of a rear window resistive defroster. The apparatus uses a confining guide edge of predetermined configuration for setting a datum or base line for the heating lines, a translation carrier mounted to the confining guide edge and confined thereto except for translation therealong, a rigid bar secured to the translation carrier through a suitable pivotable foot and locking means therefore, and a conductor laying head supported to the rigid bar and positioned at anyone of a plurality of predetermined points along the rigid bar.