The invention relates to closure, in particular syringe closure for sealingly closing a distal opening, for example a syringe cone of a syringe body, the closure, in particular the syringe closure comprises a disposed on the syringe body around the distal opening, in particular the syringe cone around or which can be arranged fastening member and the distal opening , for example, sealingly closing the syringe cone and includes with the fastening element detachably connected to the closure cap, characterized in that the fastening element comprises an internal thread engaged with an external thread of the closure cap in engagement, yielding an initial state wherein the external thread is formed on at least a portion of the closure cap wherein the portion under tension, such that after unscrewing the cap from the internal thread the stressed portion on the internal thread of Befestigungsele ment is pushed out, so that the closure cap can not be brought back into the initial state after the unscrewing of the closure cap.