Used in a series of triggers with other buttons (Super and/or small) or High Energy Pellet receivers, these Super Buttons commonly seen on floors must be activated by a Test Subject in order to receive other testing elements, open up wall panels, or most commonly, to unlock the chamberlock doors.
The Edgeless Safety Cube Receptacle in Portal 2 serves the same purpose as the Super Buttons, but only for the Edgeless Safety Cubes instead. Edgeless Cubes are applicable on Super Buttons, but may roll off of it when not properly positioned.
In the Portal 2 cooperative campaign, the Super Buttons are occasionally replaced by Cube Buttons for placing Storage Cubes. This is most likely to prevent one co-op partner activating a switch and trapping the other player in the next area.
With the Sixense DLC for Portal 2 installed, the lights on the base unit of the Super Button will turn yellow if a cube is floating above it. This feature is designed to aid in depth perception when using the extended reach granted by the Razer Hydra controller.
An earlier prototype of the Super Buttons can be seen in the old condemned parts of the facility. Serving the same purpose as the later iterations, the old buttons are simplistic in design, made from a simple metal frame with spring wires under the red-painted metal sheet.
As seen in the earliest known Portal screenshot and the original Portal trailer, the Super Button may have been originally white-colored. Although this is more likely due to the fact that the Super Buttons were yet to be textured, as the white colors of the model are typical to that of models that have just received a UV map.
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Added by Klow
