Made this because there so many different box sizes and formats. Made this in Fusion360, you can change parameters to fi your needs. UPDATE 03.09.2024 - made plug placement smarter. Main: Box_width - width of your box Box_height - height of your box Plug_quantity - how many plugs you want for your box (2 recommended, you can experiment with them, distance betveen plugs have 25mm step) Wall_height - overall height of holder, be creative! Other parameters are static, but you can try to change them if you need.