This FreeCAD design is to make simple vice claws with a single horizontal groove and three vertical grooves. You can insert two "round disc neodymium" magnets in each claw so you can install or remove them very quickly. The design is parametric and thus fully customizable to fit your vise jaws. To adjust the dimensions, open the FCSTD file with FreeCAD, then the 'Dimensions' spreadsheet in the tree view. You can have both the design and the parameters side by side by clicking on the 'Windows' menu then 'Tile'. The parameters names are self explanatory. If you don't want holes for the magnets set their thickness to 0. For no grooves, set their deepness to 0. Once you are satisfied with your settings, export the new thing in STL. When some parameters combinations are impossible, FreeCAD will either ignore your choice or just crash. I provide an STL file as example. This is an open-source design. FreeCAD file is provided. Feel free to modify this thing at your convenience. Good design is hard work, even small donations are welcome.