The Gemini spacecraft was equipped with a non-androgynous mechanism for docking with the Agena target vehicle or Augmented Target Docking Adapter.
The Gemini side of the mechanism consisted of 3 latch receptacles around the forward end (the rendezvous and recovery section) of the spacecraft.
[1] The Agena side of the mechanism consisted of a truncated cone to guide the nose of the Gemini spacecraft into 3 corresponding latches.
[2] Unlike the later Apollo Docking Mechanism, the Gemini docking mechanism did not provide internal access between the docked spacecraft; it only locked them together and provided an electronic umbilical to control the Agena from the Gemini capsule.
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