Great job making a vent for the basement range hood. It's just over 7" and fits the pipe perfectly. Could have gone up a size but still manages it. Start slow and be careful, sometimes it can catch a nail or something and the end of the saw stop it immediately which will cause the drill you are holding to start spinning which can throw your hand a lot in the process but if you do it carefully you will be fine anyway it worked great For some reason you won't find 7" bits like this at Home Depot or Lowe's, so get one if you need a 7" hole anywhere.