The prototype microwave-electrothermal-thruster (MET), designed and built by Mehmet Serhan Yildiz, is successfully tested. Unlike the tests conducted during the summer of 2015, the prototype thruster is placed on a specially manufactured port on the door of the BUSTLab vacuum chamber. Thus the thruster and all the relevant connections were outside the chamber. The thruster nozzle plate faces the inside of the chamber, thus allowing the thruster plume to expand into the vacuum of the chamber. The thruster was operated at 2.45 GHz microwave frequency with Helium propellant. Power levels of up to 500 W was delivered to the thruster during the tests. The first picture below shows the thruster attacched to the ISO-320 port on the door of the BUSTlab vacuum chamber. The second picture shows the power generation and delivery system, as well as the gas delivery and pressure measurement systems located outside the vacuum chamber. The third picture shows the discharge region of the chamber during its operation. The fourth picture shows plume exiting the nozzle of the thruster. The last picture is taken from one of the side viewports of the BUSTLab vacuum chamber.