Closure For A Container

A closure for closing a container, the container having a sealing surface extending around an internal surface, a plurality of circumferentially spaced apart thread features extending around an external surface, and a substantially circular opening defining an axis, the closure comprising:

• a cap having an upper portion;
• a skirt portion depending from said upper portion, the skirt portion comprising a plurality of circumferentially spaced apart thread features for engagement with the thread features of the container, the thread features selectively(?) spaced to enable fastening the closure to the container with a rotation of less than 360 degrees;
• a relatively rigid bore member comprising a groove formed in an outer surface;
• and
• an o-ring sealing member comprising a toroid formed of resilient elastomer material, the o-ring sealing member received in the groove in the bore member and sized to enable deformation and movement of the o-ring sealing member within said groove, wherein when the bore of the closure is extended through the opening of the container, the closure is securable to the container by rotation about the axis, the rotation engaging the thread features of the skirt with the thread features of the container, drawing the bore member into the container so as to press the sealing member against a side wall of the groove to seal a gap between the side wall and the sealing surface so the o-ring sealing member provides a seal between the bore member and the sealing surface of the container within a rotation of less than 360 degrees.