Abstract: A device for mounting panels of fibrous refractory material against the inner surface of the wall of an industrial furnace, comprising a plug of refractory material in the form of a bolt with a square head and a non-threaded cylindrical shank provided with a plurality of circular ribs arranged in planes perpendicular to the axis of the plug, the panels to be attached thereby having spaced-apart apertures of dimensions intermediate those of the head and of the ribs on the shank, and the wall of the furnace having corresponding cavities filled with a sealing material and for receiving the shank of the plug.