Abstract: A tamperproof sterile solution closure system which will permit the machine assembly of the closure cap to the container without engagement of the threads of the cap with the container threads. The screw type cap member has internal threading, a tear-away portion and a skirt portion. The container has an abutment surface for sealable contact with the skirt portion and in a position such that the threads in the cap and on the neck are not engaged. To activate the closure, a tear-away portion is removed which will allow the threads to engage. Simultaneously, a contact portion on the cap will engage a weakened flange in the neck to cause it to be separated. A projection extending from the cap is positioned in an annular recess in the cap to serve as a captive means for the separated dome portion of the cap for replacement purposes.