Shadowboxes come in all different shapes and sizes, all depending on the contents that they are displaying. Some objects are larger than others and require a deeper frame. Keep this in mind when deciding to frame your memorabilia. If you are not concerned with protection it is always an option to frame without glass witch can give you more choices in the types of frames you can use. Glass is always recommended, but in some cases the rules can be broken. If you need ultimate protection for your piece, use conservation glass or even better museum glass.