Save Edge square file for sharpening square ground chain. Granberg filing guide recommended if you want to square grind your chisel chain. This is for x1 chisel bit file – the files are x12 more expensive than normal chainsaw round files probably to do with the much lower production volumes. Square ground chain is incredibly hard to sharpen. However you can return square ground chain to general chisel chain by using a round file to sharpen it.
Using the Granberg clamp on file guide is essential for getting this type of chain sharpened right as then you can set and duplicate the complex angles. There is an excellent guide on how to do this here. If you are serious about square ground chain you need to read it.