A device for coupling two containers comprising connecting branches having essentially circular cross section, with each of the connecting branches having a closing member at one end, which is essentially circular in cross section, for closing the end facing away from the container. When the two connecting branches are brought together, the two closing members are combined into a single member moved by a single actuator so that no clearance is required in each of the branches between the ends of the branch and the member. Each of the branches has annular edge seals, which, in an uncompressed condition, engage a circumferential edge of each of the closing members and are compressed when engaged with the edge seal of the adjacent branch member to release the respective closing member. The edge seals coact to form a butt chamber and one of the branch connections has a circumferential sealing sleeve into which the other of the branch connections is inserted in a sealing fashion when forming a connection between the two branch connections.