Craftmaster Heavy Duty Oblong Punch
Hand-forged bag/oblong punches used by professional bag and strap manufacturers.
Before using, the tool will need to be polished to get a good result.
Tips for polishing: keep a consistent angle along the bevel, pull back slightly as you round the corners so as not to bite too deeply into the edge, and be liberal with your use of buffing compound.
This tool will get dull with use, so make sure to continue to polish the blade occasionally as you notice performance decreasing.