Our group is investigating the use of lithium for use in fusion reactor walls. Lithium is very chemically reactive, so our experiments are conducted in vacuum chambers. Our particular interest is in the properties of liquid lithium, so we need a heated container, which in this case is a circular tray that follows the "doughnut" shape of the magnetic bottle containing the hot fusion plasma. This photograph was taken during a heater test prior to filling the tray with lithium. The glowing regions outline the circular disk heaters underneath the tray.