The volume of the Electrochemical Detector thin-layer cell is determined by the thickness of the gasket used to separate the auxiliary and working electrodes. BASi® produces 0.0005", 0.002", 0.005" and 0.015" thick PET or Teflon gaskets which can be used alone or stacked in various combinations to give the desired cell thickness. The 0.0005" PET gasket (for microbore columns) appears clear, while the other gaskets look milky-white.