Caps for containers

A cap for a container or spout comprising

• a central tubular body, which extends along a central axis and is closed by a base and has a lower end on a side of the central tubular body opposite the base,
• a guarantee seal suitable for breaking when the cap is unscrewed from the container, said guarantee seal being positioned breakably connected to the lower end of the central tubular body on the side opposite the base,
• an annular wall positioned externally to said central tubular body and having a lower free rim, and an upper free rim at the base of the central tubular body, wherein said lower free rim comprises a waved pattern that annularly surrounds said guarantee seal on the side opposite the base,
• wherein the lower free rim is formed of a sequence of valleys and peaks, said valleys having a bottom being defined as a point of closest vicinity to the upper free rim and said peaks having a top being defined as a point of maximum distance from the upper free rim, and the top of the peak of at least one of the peaks has the same distance from the upper free rim as the distance of the end of the central tubular body from the upper free rim as measured longitudinally along a central axis of the central tubular body,
• wherein the peaks and valleys comprise a C/A ratio from 1.5 to 2.5,
• with C being the distance along the central axis separating the top of the peak from the upper free rim and with A being the distance along the central axis between the top of the peak and the bottom of the valley.