Storz is a type of graft also called "sexless coupling", ie a connection without sex, because rather than having a male end and a female end connected by threads, it provides that identical ends can be joined together.
The Storz joints are not screwed, but the connection is made according to the principle of a bayonet lock. it is made by joining two connections in such a way that the hooks of each go into the slots of the flange of the other; they are then rotated in opposite directions until they are close together, creating a watertight connection between the gaskets internal. The main advantage of using Storz connections is the speed: generally, a coupling can be made with a 1/4 turn where threaded fittings need to make several tightening turns to make a solid union.