Patent ID: 8522991

Claim:
A tamper-evident closure for a container, said closure comprising: a. a first portion including an inner part and an outer part, wherein said inner part comprises a disk-shaped top plate with a cylindrical skirt depending from the periphery of said top plate and wherein said cylindrical skirt has a first set of screw threads for engaging a first set of corresponding threads on said outer part and the inner surface of said cylindrical skirt has a second set of screw threads for engaging a second set of corresponding threads on said container; and b. a second portion, wherein said outer part is movable relative to said inner part from a first position in which said outer part is immediately adjacent said second portion to a second position in which there is an unobstructed gap therebetween around the entire periphery of said outer part and said second portion, said inner part and said outer part being constructed and arranged to become irreversibly locked in said second position so that said outer part cannot be moved back to said first position to close said unobstructed gap.