This envelope was on board the International Space Station.
The “Crew Dragon Demo-1”, officially known as “SpaceX Demo-1” and “Crew Demo-1”, was the first orbital test flight of the “Dragon-2” spacecraft. This first spaceflight was an uncrewed mission. The cover was marked with the “ISS” octagonal board seal, the “Russian Post. ISS. Russian Segment” round board post mark and the “Russian Segment of International Space Station” board souvenir seal both dated 3 March 2019, the day when the US “Dragon-2” spacecraft (“SpaceX Demo-1” mission) docked to the ISS. The cover was autographed by 3 astronauts who were on board the ISS on 3 March 2019: American astronaut Anne McClain, Canadian astronaut David Saint-Jacques, Russian cosmonaut Oleg Kononenko. It is necessary to remark that the cover was not carried by the "Dragon-2" spacecraft. The cover was delivered to the ISS and then back to Earth by a Russian cosmonaut aboard a Soyuz MS spacecraft.