Hermaphrodism, so there were no "male" or "female" connectors; any GR connector could mate with any other GR connector.
This last characteristic was achieved by having both the inner and outer conductors made from four leaves, two of which were displaced slightly outwards and two of which were displaced slightly inwards. By rotating one connector by 90 degrees, its inner leaves would mate with the other connector's outer leaves and vice-versa.
Adapters to other connector series were available.
Eventually, the high cost of the connector led to it being obsoleted by the much more common BNC connector and, for high-frequency applications, N connectors and SMA connectors. General Radio designed the incompatible Type 900 successor to the 874, to address the higher performance needs of the industry, but it was not very successful.