Detail of a capture latch. There are three capture
latches on the probe head.
The probe head is guided by the funnel-like drogue
on the lunar module to the receiving
hole in the drogue. The latches slip into and automatically engage the
hole, effecting "capture."
The button in the center of the probe head allows astronauts in the Lunar
Module to disengage the capture latches (e.g., in an emergency situation, when
the Command Module Pilot is not able to do so from inside the CM).