i always use the 2" hole saw but what i found is there are 3-4 manufacturers of net pots and all are slightly different in size.some are a little smaller, some fit in perfect(but will need securing from falling), and some larger. i like the hydrofarm pots, they are the most sturdy made and the slightly bigger ones. they fit nice and tight and i have no problems with them toppling over or out without securing. 200 for $20 at plantlightinghydroponics.com.