ATV-4 late-cargo loading at Kourou

Technicians inspect the docking cone on ATV-4 at Europe’s spaceport in French Guiana.

Automated Transfer Vehicles (ATVs) bring supplies to the International Space Station via Russian docking ports.

Russian docking ports have a male and female version, like an electrical plug and socket. This means that a spacecraft can dock only with a vehicle that has the correct receiving port. Here, the male version on ATV is visible.