Abstract: A tamper-proof bottle closure is formed of a readily deformable material and is threadedly securable on a bottle. The closure includes a top portion from which a skirt depends and a security band which is detachably connected to the skirt along a circumferential line of spaced slots by bridges of material located between the slots. At least one of the bridges is wider circumferentially than the remaining bridges. At least one transverse score line is formed in the security band extending upwardly and terminating in the region of the line of slots. A weakened line is provided extending across at least one of the wide bridges in alignment with the slots. The security band can thus be completely detached from the skirt without leaving a burred edge on the skirt which is apt to injure the user's hand during repeated use of the closure.