A beverage container (1) comprises a container body (3) including an opening and a cap (5) to close the opening, the cap (5) or the container body (3) including one or more bayonet threads (57), and the container body (3) or the cap (5) respectively including one or more protrusions (19) arranged to engage with a respective bayonet thread (57) to secure the cap (5) to the container body (3). At least one of the bayonet threads (57) includes one or more stop members arranged to retain the, or each, protrusion (19) substantially fully engaged with the bayonet thread (57) such that the opening is substantially fully closed by the cap (5), until a releasing torque sufficient to overcome the retention is applied to the container.