The Pure Distilling 4" Copper Bubble Plate is designed to be inserted into a 4" sight glass using a specially designed 4" Bubble Plate Seal (sold separately). 

Bubble plates increase separation efficiency during distillation by repeatedly contacting rising
vapour with liquid on each plate. Seals to fit are also available for separate purchase.
Please note that we do not recommend using bubble plates with our Pure Distilling Reflux
Condenser, or alcoengine unless the user is particularly keen to experiment. These Reflux
Condensers are liquid controlled, meaning it already has a pseudo bubble plate working inside the
tower.
If anyone is keen to try using a bubble plate in a sight glass, the system will need to be run on the
large 1700W element only once the boiler comes up to temperature. The system will enter slow
mode very early, and the run will typically take more than 5 hours. Expect plenty of activity in the
sight glass during the first hour of the run.
These are better suited for those using vapour-controlled condensers or Pot Condensers.