This tube is intended for investigation into the nature of gaseous discharge at various pressures & voltages. The tube has two removable flanged end bulb with internal phosphor coatings, a flanged body tube, two metal electrodes with 'O' ring seals an adjustable leak value for varying the pressure in the tube, and two pieces of vacuum hose. The tube fit into the Universal Stand and has been designed to work at voltages upto 5kV and pressure in the region of 10-2 to 10-5 torr.