The following is from Wikipedia
Storz is a type of hose coupling invented by Carl August Guido Storz in 1882 comprised of interlocking hooks and flanges. It is sometimes referred to as a sexless coupling, because rather than having a male and female end connected by screw threads, either identical end can be joined to any other end of the same size. This is also called hermaphroditic or two-way connection. Amongst other uses, it has been widely employed in firefighting applications.
To couple a Storz connection, the two opposing couplings are pressed together such that the hooks of each one are inserted into the slots in the flange of the other. Then they are rotated in opposite directions until they are tight, or latches engages. This creates a water-tight connection between the internal packing gaskets. To uncouple them, the latches are released and the couplings are turned in the opposite directions from coupling, and then separated when the hooks and slots are aligned. Special wrenches are designed for assisting with Storz connectors.
In the United States, fire engines typically carry LDH (large diameter hose) with Storz couplings on both ends for connections between fire hydrants and pumps. However, hydrants in the USA usually have threaded couplings and require an adapter to use with Storz. This is not the case in many other nations.
Guido Storz patented his coupling in Switzerland in 1890, and it soon became a standard for fire hydrants throughout much of Europe. However, it took nearly one hundred years before steamer ports on fire hydrants started to be converted to the Storz type in the United States. All major U.S. hydrant manufacturers now offer Storz as original equipment on their hydrants, to match the Storz couplings used by firefighters.