Abstract: A display device support arm comprises: a securing component; a first support arm element pivotally attached to the securing component and coupling to an attachment means for receiving a coupling mechanism, incorporating a load indicator, at the lower end of a second support arm element. At the other end thereof is an attachment head and a display mounting head rotatably secured thereto. The mounting head includes a toothed arcuate surface to which there is pivotally mounted a trigger adapted to move one or more locking blocks out of biased engagement with the arcuate surface. Constant friction joints, a modified securing foot with tool holder, a tilt mechanism; a display rotation lock operably coupled to a display mounting interface; interchangeable rail assemblies; display mounting brackets for attachment to the rail assemblies; and methods of installing a support arm and setting a tilt mechanism are also defined.