Thanks to the original designer Erik Cederberg at 3DVerkstan. This is a two piece design to allow single extruder stacking, using a 45 degree taper down to a line, to make separation possible without any support materials or fine tuned settings. The cover part is separated from the frame so that no bridging is needed. Separation can be a bit tricky and takes about a minute per piece, but allowing overnight printing will probably make up for that. Only the Swedish 4 hole version is available at the moment.