This is a case for the QIMSI storage and mouse port add-on for the Sinclair QL which holds the PCB firmly and gives support by fitting the opening the QL case.

The PCB slides into the shell and the back is then attached.

When printing the shell for best results rotate by 270 degrees in the Bambu slicer so that the rear is flat on the plate.

The back plate is a tight fit but isn't firm enough to hold the unit together, so a few small dabs of hot glue around the edge is enough to hold it. Laying the unit on the rear and pressing down on a table is the best way of getting the rear fully pushed in and level. You may want to do a dry fitting before gluing.