Needed some way of mounting some posters to my wall in a way I can move them easily and not destroy them when applying/removing.
After sticking them down to some foamboard to make them posterboards I designed these little keyhole plates that will grip into the foamboard and provide a keyhole to slot the posterboards onto screws on the wall.
To attach to posterboard line them up with where you want them to go. They usually move up about 2-4mm depending on how well you could get the spikes to sink in so keep that in mind. Firmly press down on the plate so that you feel the spikes penetrate the foarmboard, at this point you can use some force laterally to help the spikes slide into position.
If you want to make sure they're a bit more secure put some hot glue on the spikes and in the recessed divots under the spikes before pushing on so that they can bond together instead of relying purely on friction.
The poster I attached foamboard too and mounted was one I designed for some Onewheel Art I did that you can get here if you'd like :)