STORY: Artemyev and Matveev, engineers from Roscosmos, exited the Russian module Poisk at around 1500 GMT for a seven-hour excursion.
The main tasks of the spacewalk included the removal and jettison of thermal blankets covering the arm and the release of launch locks of it.
Footage distributed by NASA showed cosmonauts waving goodbye to the thermal blankets as they tossed them onto the space. According to NASA, they won't interfere with the station's orbit at any point.
During a first spacewalk back on April 18, the cosmonauts installed and connected a control panel for the European robotic arm, a 37-foot-long manipulator system mounted to the Nauka module.
The arm will be used to move spacewalkers and payloads around the Russian segment of the ISS.
This was the fifth spacewalk in Artemyev’s career and the second for Matveev, as well as the 250th spacewalk for space station assembly, maintenance, and upgrades.