The volume of the basolateral (lower) compartment is 1.5 ml.

The volume of the apical (upper) compartment is 1.5-2.0 ml, depending on if electrodes are used, and if the tissue ring or Snapwell culture cups is used.

1.5 ml applies for the case of a tissue ring without electrodes, and 2.0 ml applies for the case of a Snapwell culture cup with electrodes.