Prusa i3 spare steel sheet holder (not for the mini). I wanted a holder that has sufficient height and a nice form. This one has enough spacing for each sheet an can be screwed with SPAX 3x30 (or short, longer ones) screws to any table from below.
For stackable mounting start printing sheet-holder and then sheet-holder-below (for any subsequent) which helps adjustment. For left and right versions, please use the mirror function in your slicer. Please note, some photos show an older version.
I attach the original inventor for remixes.
The author hasn't provided the model origin yet.