Abstract: A screw cap comprises a main cap portion 1 having screw threads on its inner circumferential surface and a number of splines 6 axially extending on its outer circumferential surface, and a ring portion 11 having a projection 12 on its inner circumferential surface and a number of splines 13 extending on its outer circumferential surface and continuous from the splines 6 of the main cap portion. The ring portion 11 is spaced apart from and connected integrally with the lateral wall of the main cap body by fragile connector strips 15 which are partial extensions of the splines 6 or 13 lying over the distance A between the main cap body 1 and the ring portion 11. Thus the cap has a totally uniform, continuous appearance suitable for containers of products which should desirably look high-graded or uncontaminated.