pickle jar. A trick about thumpers is if it starts to get full splash a small amount of water on the top of your still. It will create a suction and empty your thumper. After your alcohol production percent will go up higher for a short period of time after doing that also.
Or bigger the better but the bigger the longer it takes to heat your really better off running a couple small thumpers in a row and like i said pickle jars work perfect. Anyone says they can blow up is not a shiner they are full of bs and should not be making shine if they are stupid.