Abstract: A cap with a rotatable skirt (1), applicable to the mouth (6) of a container (7) for a fluid dispensable via the cap, which can also act as a closure cap. The cap comprises a skirt (1) rotatable on the mouth (6) of the container (7) and defines a cavity housing a hollow body (2) connected to the skirt (1) by breakable teeth (4), the skirt (1) and the hollow body (2) being formed in one piece by moulding. Between the skirt (1) and the hollow body (2) there extends an axially translatable cup-shaped body (3) connected to the skirt (1) by a disc (19) housed in a seat (21) provided on the top of the skirt (1), this disc (19) being moulded in one piece with the cup-shaped body (3), to which it is connected by breakable teeth (20).