<p>A device (10) for detecting an elongated metal object located behind a surface, the device comprising: a housing (24) having a substantially smooth contact face, a magnet (30) fixedly received within the housing (24) and configured for attracting the housing (24) to the surface and staying in contact with said surface, a marking arrangement (41) received within the housing (24) and at least partially projecting from said contact face and configured for generating a visible mark on said surface when the device (10) is displaced along the surface and a pulling member (50) articulated to the housing (24) for displacing the device (10) along an expected orientation of the metal object.</p>
