The present invention provides an improved system for securing a display device mounting bracket to a surface mounting bracket in a mounting system. A fastener connects to a movable extension component that is movably engaged with the device mounting bracket. When a device mounting bracket has been correctly positioned relative to the surface mounting bracket, the movable extension component is moved until a portion of the surface mounting bracket is positioned between the device mounting bracket and the movable extension component, thereby preventing the device mounting bracket from moving away from the surface mounting bracket.