The Androgynous Peripheral Attach System serves two functions on the International Space Station. It is used to dock the orbiter and to connect the Functional Cargo Block (Zarya) to Pressurized Mating Adapter 1. The system has a capture ring that extends outward from the device on the station and captures the identical device on the docking vehicle. The capture ring aligns them, pulls them together and deploys 24 structural hooks, latching the two systems with an airtight seal. Other docking ports on the Russian station modules use the same system for the docking of Russian spacecraft.

The Androgynous Peripheral Attach System was designed by Moscow-based RSC Energia and has roots in the Apollo-Soyuz program. Its current design is based on that of the Androgynous Peripheral Docking System used in the Shuttle-Mir program.