Figure 1-15. Kontakt docking system. Never used in space, the system was designed for the Soviet lunar program. The Aktiv unit (top) was located at the front of the L2, while the passive unit was located on top of the L3 lander.

Carried a spring-loaded probe docking system, called Aktiv (“active”), which was designed to penetrate and grip a “honeycomb” drogue docking fixture on the L3. Together they were called Kontakt (figure 1-15). The docking system was to be used only once during the mission, after the L3 had completed its lunar landing mission and returned to orbit. Little docking accuracy was required to link the spacecraft firmly enough to let the moonwalking cosmonaut return to the L2 by EVA.
Mir Hardware Heritage. NASA Reference Publication 1357 (March 1995).
David S. F. Portree / NASA