Its a jewelry store. walls are hollow and do not go up to the roof. It stops about 12" from the roof line. there is some type of fire resistant paneling(which doesnt look thick, but its not cinder block). the register is deep in the store with full length counter and watch bench side by side(providing cover). all the jewelry cases are made of glass including store front jewelry cases followed by large pane's of 1/2 glass approx. I have thought about the glaser saftey slugs, but am very concerned about their ineffectiveness to stop someone. i appreciate all the input so far.