The collapsible hook is designed to be constructed using the process of aluminium extrusion. Two parts are required for this hook. Below is a dimension profile of each part which would be placed on an extrusion die. 

The two extruded parts are cut to 100 mm in width, which slide into one another in order to form the hook. The clearance gap between the two parts is 0.25 mm. This facilitates an easier hinge-like movement between the two parts. The clearance gap is small enough to ensure the collapsible portion of the hook will not slip out if an item is hung on it. 

Once assembled, the hook ought to hold a weight of approximately five kilograms. 

The model above shows the development of the hinge mechanism. This model is the basic shape indication before additional reinforcing structures have been added in. 

For the prototyping of this hinge, the CAD parts (as seen below) have been 3D printed using ABS. 

Once the two extruded and cut parts (left) are joined to one another, the hinge mechanism would have a 90 degree movement ability. The part which would be attached to the wall (i.e. the part further to the back in the image on the left), would stop moving when the front section is perpendicular to it. It would not extend further down as there is a 'stop' portion added into the front part (right). 

The image on the left shows the hook in an extended position. It is not fully extended in this image, however it illustrates the way the hinge is moving towards the 'stop' portion. To the right is the hook collapsed and neatly tucked away. 

This collapsible hook/hinge mechanism can be attached to the wall using screws appropriate to the wall type. The screws are placed through the countersink holes visible in the above image. 

Various hooks can be mounted together and in different orientations in order to create a spatially unique and environment-specific design that the user would determine.