Abstract: A bar has at least one compartment, a plurality of removeable magazines mounted in the compartment, fiber optics associated with the bar compartment and each magazine for assisting to detect the removal of a magazine from the bar compartment and the removal and/or movement of the contents of the magazine. The fiber optics comprise:(a) optical fibers secured to each magazine and lenses secured to the optical fibers on each magazine; and(b) lenses on the bar associated with the compartment. Some of the lenses on each magazine are spaced from, and aligned with, some of the lenses on the same magazine for the transmission of light therebetween, and some of the lenses on each magazine are spaced from, and aligned with, some of the lenses on the bar associated with the compartment for the transmission of light therebetween.