The terms Androgynous Peripheral Attach System (APAS), Androgynous Peripheral Assembly System (APAS) and Androgynous Peripheral Docking System (APDS) are used interchangeably to describe a Russian family of spacecraft docking mechanisms, and are also sometimes used as generic names for any docking system in that family. A system similar to APAS-89/95 is used by the Chinese Shenzhou spacecraft.
APAS-75 (American version)
Drawing of a four-guide docking system that NASA proposed to the Soviets during a November 1971 meeting in Moscow
Passive
Passive (The geometry of the mating and latching features are still androgynous, but this variant is intended to reduce docking impact with additional position control on one side. either side can still be used together with either side, but mating two active sides would be unnecessary.)
Nauka (ISS module)
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Nauka, also known as the Multipurpose Laboratory Module-Upgrade or simply Multipurpose Laboratory Module (MLM), is a module of the International Space Station (ISS). The MLM-U is funded by Roscosmos. In the original ISS plans, Nauka was to use the location of the Docking and Storage Module (DSM). Later, the DSM was replaced by the Rassvet module and Nauka was moved from Zarya's nadir port to Zvezda's nadir port.
Experiment Airlock berthed and Soyuz MS-23 docked Nauka; Egressing payloads outside the station
A Russian Research Module docked to Zvezda (left) and MLM docked to Zarya (right) in an early 2000s concept.
Nauka undergoing tests at Khrunichev in July 2020, a month before it was shipped to Baikonur.