Description of MAGBIT 624 2016 MAG624 4 Inch Holesaw
1-3/4-Inch depth, 4/6 variable pitch tooth combination reduces vibration. Tough 3/16-Inch thick back plate. Deep gullet design for improved chip removal. Cuts through 2-Inchx4-Inch in one easy pass. Faster cutting and more holes per saw.
makes a big hole in drywall or wood. Then I tried to make a hole in the sheet metal. Well , it made a hole :) bad I can't use it anymore I knew it wasn't for metal I had no alternative Anyway if you want a good round as long as you take your time you will this will work for you.
Pros
Variable pitch 4/6 1-3/4" deep tooth combination reduces vibration