A container for transporting and storing a liquid and with a dual function closure, the container comprises a container body with at least one inlet opening closed by a cap. The cap comprises a first and a second opening, as well as a first closure insert and a second closure insert. The first and second openings are each surrounded by a respective circumferential wall that comprises a shoulder. Each closure insert releasably engages with the respective shoulder such that the respective opening is fluid tightly closed. The cap comprises a locking means adapted to engage with a locking interface of a coupling device.