Abstract: A cap (1) for a container having a screw threaded opening comprising an inner part (3) in the form of a screw threaded cap, an outer part (2) the inner part (3) being axially displaceable relative to the outer part (2) and biased therefrom between an unlocking and locking position, resilient biasing means (17) between the inner and outer parts, a boss (6), and engagement means (15) adapted to engage with the boss upon (6) depression of the outer part (2), such that turning the cap will unscrew it from the container wherein one of the boss (6) or engagement means (15) is located on the top surface of the inner part (3) and the other is located on the inner top surface of the outer part (2).

Abstract: A cap for a container having a screw threaded opening comprising an inner part (1) in the form of a screw threaded cap, an outer part (2), biased therefrom in a first, locking position, by means of resilient biasing means (3) located between the inner and outer parts, a projection (4) located on the inner part (1) and adapted to be received in an aperture (8) formed in the outer part (2), and a tamper-evident member (6) secured on the outer top surface of the outer part (2) such that it substantially covers the aperture (8), wherein on first removing the cap from the container the outer part (2) is moved into a second, unlocking position, against the biasing, the projection (4) being received in the aperture (8), and projecting therebeyond, such that at least a portion of the tamper-evident member (6) is ruptured.