Figure 3-10. Lyappa arm. Modules for Mir’s lateral ports first dock at the front longitudinal port. Each module carries a Lyappa arm (top), which attaches to a socket (bottom) on the outside of the Mir multiport node. The arm then pivots the module to the proper lateral berthing port.

Lyappa arm (figure 3-10) attached to a fixture in the Mir base block’s multiport docking node and pivoted Kvant 2 from the front longitudinal port to its assigned lateral port (figure 3-11). Kristall, Priroda, and Spektr also carry the Lyappa arm.
Mir Hardware Heritage. NASA Reference Publication 1357 (March 1995).
David S. F. Portree / NASA