Abstract: A closure device includes a base (1) and a top (23). The base (1) has an aperture (13) and the top (23) has an aperture (27). The top (23) is movable laterally relative to the base (1) between a first position in which the aperture (13) of the base and the aperture (27) of the top are not in alignment and a second position in which the apertures are in alignment. Biasing spring (22, 43) is provided with in the top so as to extend laterally between the base and the top with a free end of the biasing spring urging the top towards the first position in which the apertures (13, 27) are not in alignment.

Abstract: A closure device includes a base (1) and a top (23). The base (1) has an aperture (13) arranged within a surface of predetermined configuration. The top (23) has an aperture (27) arranged within a surface of complementary configuration to the surface of the base, the surface of the top being positioned adjacent to the surface of the base so as to inhibit the passage of material between the two surfaces. The top (23) is adapted to be movable laterally relative to the base (1) between a first position in which the aperture (13) of the base and the aperture (27) of the top are not in alignment and a second position in which the apertures are in alignment. Biasing means (22, 43) is provided within the top so as to extend laterally between the base and the top with a free end of the biasing means urging the top towards the first position in which the apertures (13, 27) are not in alignment.