I use Mainstays large 17 gallon heavy duty plastic containers with rope handles for planters and I have not been able to drill holes in them large enough to properly drain - plus the soil , on which they stand court. clayey and clogged them up so my plants couldn't drain. Solution: this tool. What I did was make about 12 inch holes from the bottom above the bottom near the base of the tubs so they could drain off the bottoms of the tubs. Problem solved. Note: If you are attempting to drill holes in an empty tub, you should only drill the bottom holes. If you drill side holes in an empty tub, the plastic will crack. However, if you already have a planter filled with soil, you can easily drill the side holes to give you a choice: drill the bottom when the tub is empty, drill the bottom on the sides just above the ground when it is empty is filled with earth.