SummaryThis is an end cap for a misumi style 30x30 t-slot extrusion.InstructionsThere are two STL files, one with a hole, one without. More importantly, there is an openscad script to create your own. There is a variable at the beginning called "undersize" that you can use to adjust the fit for your printer and extrusions. It would also be pretty easy to modify it for different sized extrusions. I'm not sure what the slot geometry is like for other manufacturers, I don't know if it will work for them.