Abstract:
A base (10) integral with a barrel (4) which traverses the opening (6) carries a lever (16) with two branches (17, 18) of which an opposite side (24) is hinged in an extension (30a) and whose extremity ridges bear against the back face (12) of the panel (7). A single screw (35) allows to control the pivoting motion of the lever (16) towards the panel. Application to the fixing of control and/or signalling apparatuses in openings of electric installation panels.